Yerkes, Robert Mearns [ed.]. Psychological Examining in the United States Army. United States Surgeon-General's Office. Division of Psychology. U.S. Government Printing Office, 1921.

Yerkes, Robert Mearns [ed.]. Psychological Examining in the United States Army. United States Surgeon-General's Office. Division of Psychology. U.S. Government Printing Office, 1921.