APA (7th ed.) Citation

Hetzel, M. L., & Hetzel, C. W. (1969). Relay circuits for psychology. Appleton-Century-Crofts.

Chicago Style (17th ed.) Citation

Hetzel, Michael L., and Carol W. Hetzel. Relay Circuits for Psychology. New York: Appleton-Century-Crofts, 1969.

MLA (9th ed.) Citation

Hetzel, Michael L., and Carol W. Hetzel. Relay Circuits for Psychology. Appleton-Century-Crofts, 1969.