Cita APA (7th ed.)

Spencer, T., & Purves, A. C. (1966). Selected essays. Rutgers University Press.

Cita Chicago (17th ed.)

Spencer, Theodore, i Alan C. Purves. Selected Essays. [New Brunswick, N.J.]: Rutgers University Press, 1966.

Cita MLA (9th ed.)

Spencer, Theodore, i Alan C. Purves. Selected Essays. Rutgers University Press, 1966.