Dyfyniad APA
Bopp, R. E., & Smith, L. C. (2011). Reference and information services: An introduction (4th ed.). Libraries Unlimited.
Dyfyniad Arddull Chicago
Bopp, Richard E., and Linda C. Smith. Reference and Information Services: An Introduction. 4th ed. Santa Barbara, Calif: Libraries Unlimited, 2011.
Dyfyniad MLA
Bopp, Richard E., and Linda C. Smith. Reference and Information Services: An Introduction. 4th ed. Libraries Unlimited, 2011.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.