Cita APA (7th ed.)

Helson, H., & Bevan, W. (1967). Contemporary approaches to psychology. Van Nostrand.

Cita Chicago (17th ed.)

Helson, Harry, i William Bevan. Contemporary Approaches to Psychology. Princeton, N.J: Van Nostrand, 1967.

Cita MLA (9th ed.)

Helson, Harry, i William Bevan. Contemporary Approaches to Psychology. Van Nostrand, 1967.