Thinking and Speaking
http://www.marxists.org/archive/vygotsky/works/words/

Vygotsky, Lev
Marxists.org
1934

Abstract:

This book is a study of one of the most complex problems of psychology, the interrelation of thought and language. As far as we know, it has not yet been investigated experimentally in a systematic fashion. We have attempted at least a first approach to this task by conducting experimental studies of a number of separate aspects of the total problem.