Cita APA (7th ed.)

Hirsh, H. L., & Putnam, L. E. (1958). Penicillin. Medical Encyclopedia.

Cita Chicago (17th ed.)

Hirsh, Harold L., i Lawrence E. Putnam. Penicillin. Nueva York: Medical Encyclopedia, 1958.

Cita MLA (9th ed.)

Hirsh, Harold L., i Lawrence E. Putnam. Penicillin. Medical Encyclopedia, 1958.