Robertson, I. (1981). Sociology (2nd ed.). Worth Publishers.
Lua i Stíl Chicago (17ú heag.)Robertson, Ian. Sociology. 2nd ed. New York: Worth Publishers, 1981.
Lua MLA (9ú heag.)Robertson, Ian. Sociology. 2nd ed. Worth Publishers, 1981.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.