O'Brien, R., & Soderman, J. (1975). The Basic guide to research sources. New American Library.
Lua i Stíl Chicago (17ú heag.)O'Brien, Robert, agus Joanne Soderman. The Basic Guide to Research Sources. New York: New American Library, 1975.
Lua MLA (9ú heag.)O'Brien, Robert, agus Joanne Soderman. The Basic Guide to Research Sources. New American Library, 1975.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.