Cita APA (7a ed.)

Knapp, R. J., & Capel, W. C. (1979). Drug use among the elderly. Journal of drug issues.

Cita Chicago Style (17a ed.)

Knapp, Ronald J., y William C. Capel. "Drug Use Among the Elderly." Journal of Drug Issues 1979.

Cita MLA (9a ed.)

Knapp, Ronald J., y William C. Capel. "Drug Use Among the Elderly." Journal of Drug Issues, 1979.