APA (7th ed.) Citation

Bopp, R. E., & Smith, L. C. (1991). Reference and information services: An introduction. Libraries Unlimited.

Chicago Style (17th ed.) Citation

Bopp, Richard E., and Linda C. Smith. Reference and Information Services: An Introduction. Englewood, Colo.: Libraries Unlimited, 1991.

MLA (9th ed.) Citation

Bopp, Richard E., and Linda C. Smith. Reference and Information Services: An Introduction. Libraries Unlimited, 1991.