edited by David Rubel
H. Holt, 1998
Buku Teks
Keogh, James Edward
McGraw-Hill, 1977
Buku Teks
Robert Maynard Hutchins, editor in chief
Encyclopaedia Britannica, Inc., 1952
Buku Referensi
Black Dog & Leventhal Publisher, Inc, 2004
Buku Teks
edited by William Wels
Lippincott Williams & Wilkins, 2003
Buku Teks