A study of the nature of difficulty
By: by Jacob S. Orleans ...
Series: Teachers College, Columbia University. Contributions to education -- no. 206.; Contributions to education -- no. 206.
Publisher: Teachers College, Columbia University
Published: 1926
Place of publication: New York City
Language: eng
Number of pages: 39
Subjects: Educational tests and measurements.; Educational psychology.
Other titles: Difficulty, A study of the nature of.
Notes: Published also as thesis (Ph. D.) Columbia University, 1926.

Bibliography: p. 38-39.