Cita APA (7a ed.)

Barton, T. K. (1996). USMLE step 1 (2nd ed.). Appleton and Lange.

Cita Chicago Style (17a ed.)

Barton, Thomas K. USMLE Step 1. 2nd ed. London [etc.]: Appleton and Lange, 1996.

Cita MLA (9a ed.)

Barton, Thomas K. USMLE Step 1. 2nd ed. Appleton and Lange, 1996.