A stem is that part of a word to which grammatical Affixes are added.
A stem is a part of word not changed after removing the Affixes and Prefixes while A root is a form which is not further analysable.
University of Prishtina
African University Ahmed Draia - Adrar
University of São Paulo
Punjab University College of Information Technology
University of Texas at Arlington
Centre for General Linguistics
The Dwight School