APA (7th ed.) Citation

Hunter, C., Hunter, F. G., & Buck, R. (1979). Angels on assignment. Hunter Books.

Chicago Style (17th ed.) Citation

Hunter, Charles, Frances Gardner Hunter, and Roland Buck. Angels on Assignment. Houston, Tex.: Hunter Books, 1979.

MLA (9th ed.) Citation

Hunter, Charles, et al. Angels on Assignment. Hunter Books, 1979.