Cita APA (7a ed.)

Ladd, G. T. (1897). Primer of psychology. Charles Scribner's Sons.

Cita Chicago Style (17a ed.)

Ladd, George Trumbull. Primer of Psychology. New York: Charles Scribner's Sons, 1897.

Cita MLA (9a ed.)

Ladd, George Trumbull. Primer of Psychology. Charles Scribner's Sons, 1897.