Billington, N. (1984). Animal forms. Longman.
Lua i Stíl Chicago (17ú heag.)Billington, Nigel. Animal Forms. London: Longman, 1984.
Lua MLA (9ú heag.)Billington, Nigel. Animal Forms. Longman, 1984.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.