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The parcel locker location issues: an overview of factors affecting
their location
Alexandra Lagorio 1, Roberto Pinto1
1 Department of Management, Information and Production, University of Bergamo, viale Marconi 5, 24044,
Dalmine (BG)
{alexandra.lagorio@unibg.it, roberto.pinto@unibg.it}
Abstract. With the spread of e-commerce, there has been an upsurge in the number of B2C
deliveries. The limits of home delivery such as the difficulty in finding the exact addresses
and the missing deliveries, exhacerbate the negative impacts of last mile logistics (i.e.,
congestion and pollution) To overcome these problems, solutions such as delivery to
supervised or automated points have become more and more widespread. For this reason,
there are several case studies aimed at understanding which are the best locations for these
type of solutions. The objective of this paper is to identify the main factors affecting parcel
lockers.
Keywords: “parcel lockers”, “parcel lockers location”, “location problems”, “e-commerce”, “case
survey methodology”
1. Introduction
The sudden changes and developments in the last mile delivery segment over the last fifteen years are
mainly due to the growth of B2C and e-commerce [1]. Consumers nowadays are less inclined than in the
past to wait for goods because of the Amazon effect [2]: they want the opportunity to buy at any time, any
day, from anywhere and beyond this they are looking for a service available and accessible 24/7 making
delivery operations more complicated from the point of view of the Courier, Express and Parcel (CEP)
delivery companies [3]. In the case of missing deliveries , Logistics Service Providers (LSP) have several
negative impacts such as idle time and costs. Home delivery has itself some intertwining limits: by
delivering the goods door to door it is not possible to optimally consolidate the deliveries as for the B2B
deliveries, longer delivery rounds are made, making more stops for loading/unloading, not always using
the vehicle at full load. These limitations contribute to all the other negative aspects of urban freight traffic
such as congestion, pollution, and an increase in the risk of accidents [4]. Further, home delivery may not
represent the best solution anymore due to the modern lifestyles: most people work during the day, so there
is a need to find an alternative that can satisfy both the customer and the CEP companies [5]. To overcome
these issues, over the last decade the postal operators have decided to invest in offering value-added
services, such as delivery to supervised or automated collect points. These new delivery options offer a
viable alternative to home delivery, meeting the needs of end consumers.
These alternatives, commonly grouped under the name of Collection-and-Delivery Points (CDP) solutions,
can be classified into two main groups: i) pick up points, and ii) automated locker boxes (also called parcel
locker or smart lockers or parcel banks). Pick up points are usually shops and business activities used as a
delivery point for the courier where customers could go to retrieve their parcels. Parcel lockers, instead, are
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unattended CDP installed in public areas, where parcels are retained for a limited amount of time during
which the customer can retrieve them by using the order reference code.
One of the main issues hindering the spread and use by customers of these two forms of alternatives to
home delivery lies in the correct location of this type of solution. In particular, the efficient location has to
be chosen in order to maximise the customers’ satisfaction and willingness to use it, thus, it is necessary to
make the use of these type of solutions as "comfortable" as possible. This research focuses on parcel lockers
in particular, because their location has some more constraints (i.e., less security and accessibility,
interaction with a machine) then an attended pick-up point in a shop or in a supermarket and also more
potentiality (i.e., availability 24/7 and not only during the days and hours of opening of a shop).
Consequently, the parcel lockers are usually located in such a way that the customers do not have to vary
their daily habits. For example, one of the most common solutions is to locate parcel lockers along with
the home-work route and near the places where customers usually go when they deviate from this route
(e.g., railway stations or subways, parking lots, gas stations, supermarkets). Other alternatives are to place
the parcel lockers in places close to the point of departures (homes) or arrivals (work) of the daily trips. For
example, there are many applications of parcel lockers located in apartment buildings [6] or large
companies [7].
From these reflections, it emerges that choosing where to locate a parcel locker is not a trivial choice since
the number of potential customers that can be intercepted depends mainly on it. A wrong location could
mean a severe economic loss both in terms of expected investments that have not returned and in terms of
missed opportunities for profit. There are many models in the scientific literature regarding the location of
facilities that can also be applied in the context of the location of parcel lockers [7][8][9][10], but before
apply them it could be useful to understand what are the characteristics of the context and in particular,
what are the characteristics that must have the sites intended to host this type of solutions. This paper,
therefore, aims to understand which are the factors influencing the parcel locker location to be able to
choose in future research the models that can best be adapted to this context.
The paper is structured as follows: in the second section, a deeper parcel lockers context description
focusing on the parcel lockers working principles is provided. Then, in the third section, the methodology
used for retrieving the location characteristics is described. The fourth section discusses the factors affecting
the parcel lockers sites selection, and finally, the fifth section concludes the paper proposing further research
directions.
2. Context description
By definition, a parcel locker is a collection point usually accessible 24 hours a day, seven days a week,
365 days a year through which the customer can serve himself in complete autonomy [11]. Parcel lockers
can be used as a delivery address or as an alternative delivery location, and used as a service by logistics
operators in a customer return strategy (return management). If, for example, the first time a recipient cannot
be reached (missing deliveries) during home delivery, delivery can be made via parcel lockers.
They are usually located in easily accessible sites and near places with the high frequency of shipments and
high pedestrian traffic such as service stations, shopping centres and squares. According to a survey of users
of parcel lockers registered in the InPost database in Poland, the criteria for choosing a locker service for
customers were first of all the h24 accessibility, then the service price and the location [12]. The parcel
locker system for sending and receiving parcels is quick and convenient. All these features are reflected in
the process of purchasing, collecting and returning through the use of a parcel locker.
The entire collection/delivery process can be completed in just seven seconds, but typically takes up to half
a minute [12]. This information means that the time required is concise and, among other things, no queues
are required.
The interest of CEP companies has only recently shifted towards delivery solutions based on automatic
lockers; thus, given its recency, the adoption of this solution can be deemed not yet mature. The necessary
investments are still not transparent, and it is not yet possible to thoroughly verify the benefits and returns
from the investment in this type of solution. However, the use of lockers allows a reduction in costs and
delivery times in the last mile deliveries, without sacrificing proximity to the consumer market.
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3. Methodology
In order to analyse the main factors impacting the choice of the location for the parcel lockers, a case survey
methodology with secondary data was used.
Initially, a literature review was performed. However, only seven papers in the scientific literature using
“parcel lockers location” as research criteria were found, confirming the relative newness of the topic. Then,
a careful analysis of these papers were carried out, and main factors impacting parcel lockers location
choices were inductively identified. Table 1 summarises the results of this first literature analysis.
Table 1: Factors for parcel locker location retrieved inductively from the scientific literature
Factors
Definition
Reference
Availability
Possibility for delivery and collection of
parcels 24/7
[12][11]
Accessibility
Degree of connection with the different
infrastructures and modes of transport
[13][14][12][15][16]
Security
The state of being free from danger or threat
[13][15]
Environmental
Impact / Land
occupation
How parcel lockers impact on the
environment in terms of emissions and land
occupation
[13][12][15][11]
Costs
Estimate price of the installation and
maintance of the parcel lockers
[7][12][15]
Methods of use
Procedures to implement to use the parcel
lockers
[14][12][11][16]
Regulations
Official rules issued from different countries
in order to regulate parcel lockers activity
[12]
Because of the small numbers of papers found in the scientific literature, the research was extended also to
the analysis of real case studies through the use of secondary data. The case survey methodology allows
identifying patterns and performing tests across different case studies [17] overcoming the problem of
generalising from a single case study, thus providing more in-depth analysis of complex organisational
phenomena than questionnaire surveys [18]. Secondary data were used to overcome some limitations of
this method (i.e., lack of data, heterogeneity of data, different levels of precision of the data available) [19].
Secondary data can be defined as data collected by others, not specifically for the research question at hand
[20]. In the case of this research, the term secondary data mainly refers to data collected by companies (i.e.,
annual activities report, financial data, official website). Moreover, data from press (i.e., newspapers
articles, websites) and grey literature (i.e., not published academic researches, reports, white papers) have
been taken into consideration.
According to the case survey methodology proposed by [18], a group of relevant case studies for the
analysis of parcel lockers location have been analysed according to the factors impacting location choices
that came out inductively from the literature review previously discussed. The analysed cases are
summarised in Table 2.
Table 2: Case study analysed form companies implemented parcel lockers in Europe
Company
Country
Type of
company
Analysed
service
Source*
Australia
Post
Australia
Postal
operator
MyPost
https://auspost.com.au/
La Poste
France
Postal
operator
Pickup Station
lockers
https://www.pickup.fr/pudo/pickup-station-
en.sls
Bpost
Belgium
Postal
operator
Cubee
https://cubee.be/
CTT
Portugal
post
Portugal
Postal
operator
ctt24h
https://www.ctt24h.pt/
HongKong
Post
Hong Kong
Postal
operator
iPostal Station
https://www.hongkongpost.hk/en/receiving_
mail/ipostal/index.html
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PostNord
Denmark
Postal
operator
PostNord
+SwipeBox
https://www.postnord.com/
Posti
Finland
Postal
operator
smartpost
https://www.posti.fi/en/private/receiving-of-
item/picking-up-from-locker
Poczta
Polska
Poland
Postal
operator
Poczta Polska +
SwipeBox
https://www.posti.fi/en
Swiss Post
Switzerlan
d
Postal
operator
MyPost24
https://www.post.ch/en/receiving-
mail/receipt-locations/my-post-24
USPS
USA
Postal service
provider
Gopost
https://gopost.usps.com/go
InPost
Poland
Postal and
parcel lockers
service
provider
Paczkomaty
https://inpost.pl/
Keba
Austria
Parcel locker
Provider
KePol
https://www.keba.com/en/logistics-
solutions/products/lockers/lockers
Correos
Spain
CEP company
CityPaq
https://www.correos.es/
DHL
Germany
CEP company
packstations
https://www.dhl.de/en/privatkunden/pakete-
empfangen/an-einem-abholort-
empfangen/packstation-empfang.html
UPS
USA
CEP company
Access Point
https://www.ups.com/it/en/services/individua
l-shipper/ups-access-point-deliveries.page
Cainiao
Network
China
CEP company
Cainiao Post
https://global.cainiao.com
Amazon
USA
Online
shopping
platform
Amazon Lockers
https://www.amazon.com/b?ie=UTF8&node=
6442600011
* for space constraints, only the main websites referring to the services mentioned are listed. The complete list of secondary data
used for research on white papers, reports and newspaper articles is available on request.
The use of the case survey methodology with multiple sources enhanced both the reliability and validity of
the study [21], but there are also some limitations. The use of information form different sources and the
need to codify the contents the secondary data for extracting homogeneous, unique and well-defined
factorsinevitably leads to a simplification of the process.
4. Results and discussion
This section analyses the factors that influence the parcel lockers location according to the performed
literature review, and the roles that these factors play in several real case studies of parcel lockers
implementation projects.
4.1. Availability
The customer's concern is represented by the delivery time and the risk of non-delivery. According to
PostNord [22], most clients use lockers at times when branches are closed or at weekends. Parcel lockers
can, therefore, be the solution to these types of problems, because they are one of the most flexible methods
and are available 24 hours a day, seven days a week. If located in supermarkets, shopping malls, or post
offices, they do not allow a 24/7 coverage: in this case, the hourly flexibility is reduced and depends on the
opening hours of the place where the locker is located.
Greater time available for the pickup operations made by customers allows to have a broader range of
customers who are available at the parcel reception at very different times. The ability of the buyer to travel
to the site once they are finished working or at the weekend avoids having to postpone the time of collection
and sacrifice time during the day that would otherwise be engaged in other activities. In other cases, hourly
flexibility becomes a factor that favours the courier, guaranteeing the possibility of planning and making
deliveries at off-peak times, in the early morning or the evening according with the analysed CEP
companies projects (UPS, DHL, Cainiaio, Correos).
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In addition, the shorter parcels storage time in the lcokers should be considered: the reduced space dedicated
to the storage of the goods and the high turnover (considered as the use of lockers and the need to have free
space to position the products) allow in most cases a stay between three and five days. The greater ease
and rapidity of access to lockers already allows customers to pick up the ordered goods more comfortably,
not requiring a further extension of the parcel storage time.
4.2. Accessibility
The accessibility of a parcel locker depends on its location and the concentration of the market in the served
area. It is therefore essential to have a positioning and coverage strategy outlined by couriers and other
operators at the design stage. As a result, the number of lockers and their geographical location impact the
effort that the customer must make to collect the order. Increasing the number of locations distributed
throughout the territory increases the capillarity and proximity of these to the end-user.
The customer will find more easily a comfortable locker, and that requires the least possible deviation from
the places that presides so that the locker integrates with the daily journey of the customer. Besides, it can
also be challenging to ensure secure locker locations and to ensure the safety of customers and their parcels
at potentially dangerous times and places.
In order to maintain a high occupancy rate, the locker must also be efficient. According to InPost, DHL and
LaPoste the best locations for this type of measurement, taking into account the concentration density of
the population, are also linked to their availability are mainly metro stations, bus stations, industrial areas
and high-traffic areas, service stations, shopping centres, supermarket car parks, schools and universities,
bank ATMs.
4.3. Security
In order to assess the safety of the delivery models, it is necessary to determine the factors that depend on
the delivery process and the volume of products delivered. The first parameter considered for all the projects
analysed is “delivery success", which is the real possibility to know if the product has been delivered and
then be able to verify the delivery. The second parameter is the use of cameras that record 24 hours a day
what happens at the delivery points according with Keba and InPost. Finally, real-time connectivity with a
private or local police security system must be considered and this is a common solution for national post
operators such as LaPoste, Bpost, Posti and Swiss Post.
In the case of an attended delivery, the courier can have the customer sign a document when he receives
the package. In this way, the couries has a document that certifies the success of delivery. It is not possible
to guarantee success from the moment the courier deposits the package leaving it at the customer's home
without the signature. On the contrary, successful delivery to the parcel lockers takes place when the courier
deposits the package in the locker and closes it. For this factor, the locker is a more than safe solution even
if the courier must be careful to guard the truck once it loads the packages into the lockers. The solution
with locker, is subject to the theft of opportunistic type, despite having security cameras and also real-time
connections. There is the possibility of being stolen after picking up the package, outside the surveillance
field of the security cameras. In order to guarantee maximum security, they are inserted in the monitored
sites (for example, petrol stations, 24-hour car parks, supermarkets). Besides, each machine has usually an
anti-intrusion mechanism through cameras for the surveillance of the terminals, which will not record the
faces of buyers (for a matter of privacy), active function unless the alarm sounds according with Keba and
InPost.
4.4. Environmental Impact / Land Occupation
Consider a simplistic delivery routing route where the courier picks up parcels from the hub, delivers at
each node if possible and returns to the sorting centre. The problems that arise with home delivery are
determined by the number of customers who are available at home at that time and the capacity of the truck
that determines the number of nodes to visit, as well as the distance between them. If customers were not
present, the problem of missing delivery is introduced, which leads to the reformulation of a second mission
for that package, leaving out another, with a further increase in environmental impacts. If a percentage of
the deliveries are destined to the parcel lockers, it means that for the mission there will be fewer points to
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visit, fewer trucks to use and consequently fewer distances to cover. By adopting this solution consistently
with many parcel lockers that allow having a certain capillarity, traffic and environmental impact decrease.
The density of lockers does not seem to influence the processes; it has an impact especially on the courier
who needs to extend its journey to fill the lockers, thus increasing emissions. However, the possibility of
travelling at full load softens the effect of this phenomenon. For this reason, if deliveries are made to a
CDP, if it does not have the capacity, the mission will not only visit one node but will also visit many nodes.
Parcel lockers can also solve this problem thanks to their modularity: it means that the cabinet can be
expanded according to the level of demand during demand peaks periods (i.e., Black Friday, Christmas,
Summer Sales) [13].
4.5. Costs
Most customers shop online because it is fast and convenient, but the delivery, in many cases currently is
not yet. The main reasons why customers change their logistics operator are lower prices, better
convenience, and comfort in receiving parcels. Both the customer and the courier are therefore looking for
the option that reduces the overall cost of delivery.
It is difficult to make a direct comparison between the different delivery options because there are many
factors involved such as the type of delivery provided by different e-commerce sites, the volume and weight
of the package, the distance to travel. All these costs can be mitigated by the possibility of not having to
manage undelivered parcels, so there is no need to make another delivery attempt, reducing stock in the
warehouse. For this reason, parcel lockers have a lower price for customers. According to postal operators
analysed, the reduction in costs using lockers is 42% compared to traditional home deliveries [23] .
Moreover, the installation of a parcel locker can also increase traffic to a store (physical or online) by
offering an opportunity for commercial space through advertisements printed on the locker, and also allows
the customer to manage cross-marketing and cross-selling operations.
4.6. Methods of use
The ease or difficulty of use influences the choice of delivery method or type of delivery adopted by the
customer. The difficulty of use takes into account particular obstacles that may arise in economic,
psychological, and intellectual form. However, there is an intellectual difficulty that is a minimum
knowledge that people must have to make use of the method used for retrieving parcel: they need at least
basic knowledge in the use of computers. For example, customers have to know how to use email and the
web tools to purchase and choose the nearest locker to pick up the package, customers have to understand
how to interact with the screen of the lockers to be able to pick up the package; however, it should not be
an activity of high difficulty because these displays are designed to facilitate its use. The inconveniences
that could be created can already be overcome by providing a telephone customer service connected to the
lockers and the inclusion of voice/commands for people with disabilities. This type of barrier is not of great
importance, because since delivery in e-commerce are considered, it is possible to assume that both the
customers and the deliveries operators have at least sufficient competences to manage the different
technological means.
The goods return could be more difficult than the delivery: to be able to return the product through the
locker is essential to use the label (including barcode) that is sent through the online request, and applying
it to the outside of the package. To open the locker door and enter the return, the customer has to scan or
type on the locker keypad the return code on the label attached to the package. The return through locker is
only available for products used for delivery in lockers, whose packaging do not exceeds the size allowed
by the locker’s boxes. The receipt of the authorisation to return must be included in the package with the
item to be returned and usually must be performed within a certain amount of days.
4.7. Regulations
The european legislation actually does not provide for specific provisions on lockers, so the current
legislation is referred to for similar cases. The locker could, therefore, be treated as a warehouse. However,
because of the lack of specific and uniform rules on the subject, it cannot be excluded that the municipal
authorities may also bring lockers back to commercial activity and as such make them subject to the
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authorisation system (or authorisation rules) provided for in the case of vending machines. Concerning the
building aspects, the installation of lockers in existing buildings does not entail the need to acquire specific
building titles.
On the other hand, the building permit, requested in many countries as Italy, is provided in the case of "free-
standing" lockers. Also, if the locker is installed in a public place, as is the case, for example, for
newsstands, a permit to occupy public land will be required with payment of municipal charges. In this
case, however, building permit will change depending on the location and type of structure. The uncertainty
of the authorisation and building regime referring to the lockers makes it desirable to intervene in order to
qualify the nature and prescribe in terms as similar and univocal as possible the titles and permits required
for its installation and use in urban areas. This is one of the main reason why it is not easy to install parcel
lockers, and there are very few companies that are able to operate in more than one country, such as Keba
and InPost that are parcel lockers providers in the most part of the projects analysed.
5. Conclusions
The purpose of this paper is to find the main characteristics that influence the choice of the positioning of
the parcel lockers. Correct positioning of the parcel lockers means being able to reach a more significant
number of potential customers and make the delivery service competitive concerning home delivery.
Moreover, the spread of the use of parcel lockers and the consequent decrease of home delivery would
mitigate the negative aspects of this last (more vehicles used for delivery, more stops and consequently
more significant congestion of the roads and emission of pollutants).
Thus, a review of the scientific literature was first made, but it showed the existence of a few articles, mostly
conference papers, which dealt with this topic as a demonstration of how the topic is still not mature and
still under study. For this reason, it was decided to apply a case-by-case survey methodology with secondary
data. The main European and non-European projects concerning the installation and use of parcel lockers
carried out by the leading companies operating in the field: postal operators, postal service providers, parcel
suppliers, CEP companies and online shopping platforms were then analysed. By analysing the websites,
reports, white papers and newspaper articles related to these projects, we confirmed and better understood
the importance and role of localisation characteristics deriving from scientific literature. In particular,
availability, accessibility, safety, environmental impact, costs, delivery times, usage and regulation
emerged as factors to be taken into account when choosing where to locate parcel depots. The paper has
some limitations: it is a first exploratory analysis aimed only at identifying and understanding the factors
that influence the location of the parcel lockers. Further research is needed to understand how and to what
extent these factors affect the choice of location, for example through the analysis of case studies to compare
the performance and degree of use of parcel lockers located in different areas with different dominant
characteristics. Also, future research should aim to understand how to use these features to build location
models to support decisions.
Bibliography
1. Chen, Q., Conway, A.: Commercial Vehicle Parking Availability and Behavior for Residential
Delivery in New York City. Transportation Research Board 95th Annual Meeting, Washington
DC, United States (2016)
2. Grosman, L.:What the Amazon effect means for retailers. Forbes communicationscouncil (2018)
https://www.forbes.com/sites/forbescommunicationscouncil/2018/02/22/what-the-amazon-
effect-means-for-retailers/#100aedb22ded. Accessed 20 September 2019.
3. Chiu, C. M., Wang, E. T., Fang, Y. H., & Huang, H. Y.: Understanding customers' repeat purchase
intentions in B2C e‐commerce: the roles of utilitarian value, hedonic value and perceived risk. Inf.
Syst. J., 24(1), 85--114 (2014)
4. Browne, M., Allen, J., Nemoto, T., Patier, D., Visser, J.: Reducing social and environmental
impacts of urban freight transport: A review of some major cities. Procedia Soc. Behav. Sci., 39,
19--33 (2012)
5. Emeç, U., Çatay, B., Bozkaya, B.: An Adaptive Large Neighborhood Search for an E-grocery
Delivery Routing Problem. Comput. Oper. Res., 69, 109--125 (2016)
8th International Conference on Information Systems, Logistics and Supply Chain
ILS Conference 2020, April 22-24, Austin, USA
6. US9120624B1 - Package Drop-off and Pick-up System - Google Patents.
https://patents.google.com/patent/US9120624B1/en. Accessed 20 September 2019.
7. Deutsch, Y., & Golany, B.: A parcel locker network as a solution to the logistics last mile
problem. Int. J. Prod. Res., 56(1-2), 251--261 (2018)
8. Lee, H., Chen, M., Pham, H.T., Choo, S.: Development of a Decision Making System for
Installing Unmanned Parcel Lockers: Focusing on Residential Complexes in Korea. J. Civ. Eng.,
23, 2713--2722 (2019).
9. Gonzalez-Feliu, J., Malhéné, N., Morganti, E., & Morana, J. (2014). The deployment of city and
area distribution centers in France and Italy: Comparison of six representative models. Supp. Ch.
For. An inter. J., 15(4), 84-99.
10. Wang, Y., Ong, T., Lee, L. H., & Chew, E. P. (2017, August). Capacitated competitive facility
location problem of self-collection lockers by using public big data. In 2017 13th IEEE
Conference on Automation Science and Engineering (CASE) (pp. 1344-1344). IEEE.
11. Zenezini, G., Lagorio, A., De Marco, A., Golini, R.: The Collection-And-Delivery Points
Implementation Process from the Courier, Express and Parcel Operator’s Perspective. IFAC-
PapersOnLine, 51(11), 594--599 (2018)
12. Lemke, J., Stanisław I.,Korczak, J.: Usability of the Parcel Lockers from the Customer Perspective
– The Research in Polish Cities. Transp. Res. Proc., The 2nd International Conference “Green
Cities - Green Logistics for Greener Cities”, 2-3 March 2016, Szczecin, Poland, 16 (January), 272-
-87 (2016)
13. Iwan, S., Kijewska, K., Lemke, J.: Analysis of Parcel Lockers’ Efficiency as the Last Mile
Delivery Solution – The Results of the Research in Poland. Transp. Res. Proc., Tenth
International Conference on City Logistics 17-19 June 2015, Tenerife, Spain, 12 (January): 644 -
-55 (2015).
14. Lachapelle, U., Burke, M., Brotherton, A., Leung, A.: Parcel Locker Systems in a Car Dominant
City: Location, Characterisation and Potential Impacts on City Planning and Consumer Travel
Access, J. Transp. Geogr, 71, 1--14 (2018)
15. Faugere, L., Montreuil, B.: Hyperconnected Pickup & Delivery Locker Networks, 4th
International Physical Internet Conference, 15 (2017)
16. Goethals, F., Leclercq-Vandelannoitte, A., Tütüncü, Y.: French consumers' perceptions of the
unattended delivery model for e-grocery retailing. J. Retailing Consum. Serv., 19(1), 133--139
(2012)
17. Lucas, W. A.: The case survey method: Aggregating case experience, R-1515-RC, Santa Monica,
CA, Rand Corporation (1974)
18. Larsson, R.: Case survey methodology: Quantitative analysis of patterns across case studies. Acad.
Manag. Rev., 36(6), 1515--1546 (1993)
19. Cowton, C. J.: The use of secondary data in business ethics research. J. Bus. Ethics, 17(4), 423--
434 (1998)
20. Stewart, D. W.: Secondary Research: Information Sources and Methods (Sage, Beverly Hills)
(1984)
21. Frankfort-Nachmias, C., Nachmias D.: Research Methods in the Social Sciences, Fourth
Edition (Edward Arnold, London) (1992)
22. PostNord: E-commerce in the Nordics (2019)
https://www.postnord.com/contentassets/9e5ef8a408834cb982f30f145a6b2208/en_e-handeln-i-
norden_halvar_2019_highres.pdf. Accessed 20 September 2019.
23. DHL: Annual report 2018: Acting Agile (2018).
https://www.dpdhl.com/content/dam/dpdhl/en/media-center/investors/documents/annual-
reports/DPDHL-2018-Annual-Report.pdf. Accessed on 20 September 2019.
