APA (7th ed.) Citation

Dunlap, K. (1912). A system of psychology. C. Scribner's Sons.

Chicago Style (17th ed.) Citation

Dunlap, Knight. A System of Psychology. New York: C. Scribner's Sons, 1912.

MLA (9th ed.) Citation

Dunlap, Knight. A System of Psychology. C. Scribner's Sons, 1912.