Grolier, 1994
Buku Referensi
Americana Corporation, 1964
Buku Referensi
Joshua Lederberg, editor-in-chief
Academic Press, 1992
Buku Referensi
editors-in-chief, Michel Hersen, William Sledge
Academic Press, 2002
Buku Referensi
Macmillan Educational Company, 1990
Buku Referensi