APA (7th ed.) Citation

Douglas, O. B., Sanders, M. S., Napier, T. G., & Hubbard, L. H. (1931). Progress in spelling ... W. S. Benson & co..

Chicago Style (17th ed.) Citation

Douglas, Oscar Berry, Mary Shipp Sanders, T. G. Napier, and L. H. Hubbard. Progress in Spelling ... Austin, Tex.: W. S. Benson & co., 1931.

MLA (9th ed.) Citation

Douglas, Oscar Berry, et al. Progress in Spelling ... W. S. Benson & co., 1931.