Cita APA (7a ed.)

Penrose, L. S., & Smith, G. F. (1966). Down's Anomaly. J & A. Churchill.

Cita Chicago Style (17a ed.)

Penrose, L. S., y George Franklin Smith. Down's Anomaly. London: J & A. Churchill, 1966.

Cita MLA (9a ed.)

Penrose, L. S., y George Franklin Smith. Down's Anomaly. J & A. Churchill, 1966.