Robert Maynard Hutchins, editor in chief
Encyclopaedia Britannica, Inc., 1952
Buku Referensi
edited by David Boucher and Paul Kelly
Routledge, 1998
Buku Teks
Baillie, James
Routledge, 2000
Buku Teks
O`Connor, David
Routledge, 2000
Buku Teks
Mounce, H.O
Routledge , 1999
Buku Teks