Cita APA (7a ed.)

Willoughby, D., Willoughby, S., Collier, M., Lewis, E., & Rees, R. (2000). The USA 1917 - 45 (1. publ.). Heinemann.

Cita Chicago Style (17a ed.)

Willoughby, Doug, Susan Willoughby, Martin Collier, Erica Lewis, y Rosemary Rees. The USA 1917 - 45. 1. publ. Oxford: Heinemann, 2000.

Cita MLA (9a ed.)

Willoughby, Doug, et al. The USA 1917 - 45. 1. publ. Heinemann, 2000.