APA (7th ed.) Citation

Seager, A., & Haupt, T. (1939). They worked for a better world. Macmillan.

Chicago Style (17th ed.) Citation

Seager, Allan, and Theodore Haupt. They Worked for a Better World. New York: Macmillan, 1939.

MLA (9th ed.) Citation

Seager, Allan, and Theodore Haupt. They Worked for a Better World. Macmillan, 1939.