APA (7th ed.) Citation

Boehm, L., Bush, J., Cherry, L., & Colby, S. (1977). Keystones. American book company.

Chicago Style (17th ed.) Citation

Boehm, Linda, Jerry Bush, Lynn Cherry, and Sas Colby. Keystones. New York: American book company, 1977.

MLA (9th ed.) Citation

Boehm, Linda, et al. Keystones. American book company, 1977.