Phillips, W. D., & Chilton, T. J. (1989). A-level biology. Oxford University Press.
Lua i Stíl Chicago (17ú heag.)Phillips, W. D., agus T. J. Chilton. A-level Biology. Oxford: Oxford University Press, 1989.
Lua MLA (9ú heag.)Phillips, W. D., agus T. J. Chilton. A-level Biology. Oxford University Press, 1989.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.