Cita APA (7th ed.)

De Vries, H. A. (1987). Fitness after 50 (3rd ed.). Scribners.

Cita Chicago (17th ed.)

De Vries, Herbert A. Fitness After 50. 3rd ed. New York: Scribners, 1987.

Cita MLA (9th ed.)

De Vries, Herbert A. Fitness After 50. 3rd ed. Scribners, 1987.