APA (7th ed.) Citation

Lewis, M., Clark, W., Biddle, N., & Allen, P. (1966). The Expedition of Lewis and Clark. University Microfilms.

Chicago Style (17th ed.) Citation

Lewis, Meriwether, William Clark, Nicholas Biddle, and Paul Allen. The Expedition of Lewis and Clark. Ann Arbor [Mich.]: University Microfilms, 1966.

MLA (9th ed.) Citation

Lewis, Meriwether, et al. The Expedition of Lewis and Clark. University Microfilms, 1966.