Rigidity: A flexible concept.

A DYNAMIC THEORY OF PERSONALITY

Kurt Lewin · The Journal of Nervous and Mental Disease · 1936 · 3.7K citations

Social Sciences, Behavioral Sciences, Psychology +7

A Simple Objective Technique for Measuring Flexibility in Thinking

Esta A. Berg · The Journal of General Psychology · 1948 · 2.3K citations

Social Sciences, Behavioral Sciences, Psychology +9

A behavioral analysis of degree of reinforcement and ease of shifting to new responses in a Weigl-type card-sorting problem.

David A. Grant, Esta A. Berg · Journal of Experimental Psychology · 1948 · 2.2K citations

Public Health, Behavioral Sciences, Psychology +12

The formation of learning sets.

Harry F. Harlow · Psychological Review · 1949 · 2K citations

Natural Sciences, Educational Psychology, Set Theory +1

The European Red Mite

Birger R. Headstrom · Science · 1928 · 1.8K citations

Veterinary Medicine, Entomology, Veterinary Parasitology +5