Thomas, A. R. (1995). Classification: Options and opportunities. Haworth Press.
Lua i Stíl Chicago (17ú heag.)Thomas, Alan R. Classification: Options and Opportunities. New York: Haworth Press, 1995.
Lua MLA (9ú heag.)Thomas, Alan R. Classification: Options and Opportunities. Haworth Press, 1995.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.