SCHAEFER, R. T. (2007). SociologyRichard T. Schaefer. McGraw-Hill.
Lua i Stíl Chicago (17ú heag.)SCHAEFER, Richard T. SociologyRichard T. Schaefer. McGraw-Hill, 2007.
Lua MLA (8ú heag.)SCHAEFER, Richard T. SociologyRichard T. Schaefer. McGraw-Hill, 2007.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.