Gerard George, A. J. B. (2012). Models of Opportunity (1.). Cambridge University Press.
Lua i Stíl Chicago (17ú heag.)Gerard George, Adam J. Bock. Models of Opportunity. 1. Cambridge University Press, 2012.
Lua MLA (8ú heag.)Gerard George, Adam J. Bock. Models of Opportunity. 1. Cambridge University Press, 2012.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.