Cita APA (7a ed.)

Pennell, M. E., Cusack, A. M., & Davis, M. (1929). Friends: A primer. Ginn and Company.

Cita Chicago Style (17a ed.)

Pennell, Mary E., Alice M. Cusack, y Marguerite Davis. Friends: A Primer. Boston ; New York ; Chicago ; London ; Atlanta ; Dallas ; Columbus ; San Francisco: Ginn and Company, 1929.

Cita MLA (8a ed.)

Pennell, Mary E., et al. Friends: A Primer. Ginn and Company, 1929.