APA (7th ed.) Citation

Powell, G. H., & Powell, L. C. (1921). Ethan Allen Chase: An appreciation. [publisher not identified].

Chicago Style (17th ed.) Citation

Powell, George Harold, and Lawrence Clark Powell. Ethan Allen Chase: An Appreciation. [Place of publication not identified]: [publisher not identified], 1921.

MLA (9th ed.) Citation

Powell, George Harold, and Lawrence Clark Powell. Ethan Allen Chase: An Appreciation. [publisher not identified], 1921.