Duby, G. (1982). The three orders: Feudal society imagined. Univ. of Chicago.
Lua i Stíl Chicago (17ú heag.)Duby, Georges. The Three Orders: Feudal Society Imagined. Chicago: Univ. of Chicago, 1982.
Lua MLA (9ú heag.)Duby, Georges. The Three Orders: Feudal Society Imagined. Univ. of Chicago, 1982.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.