Cita APA (7a ed.)

Barrows, H. H., Putnam Parker, E., & Sorensen, C. W. (1954). The American continents. Silver Burdett.

Cita Chicago Style (17a ed.)

Barrows, Harlan H., Edith Putnam Parker, y Clarence Woodrow Sorensen. The American Continents. New York [u.a.]: Silver Burdett, 1954.

Cita MLA (9a ed.)

Barrows, Harlan H., et al. The American Continents. Silver Burdett, 1954.