International encyclopedia of psychology; Volume two
edited by Frank N. Magill
Fitzroy Dearborn, 1996
 Buku Referensi
International encyclopedia of economics; Volume one
edited by Frank N. Magill
Fitzroy Dearborn, 1997
 Buku Referensi
Encyclopedia of literature; Volume two
edited by Joseph T. Shipley
Philosophical Library, 1946
 Buku Referensi
The Grolier international dictionary: volume two
Grolier Incorporated, 1990
 Buku Referensi
The New complete medical and health encyclopedia; Volume two
edited by Richard J. Wagman
J.G. Ferguson Publishing, 1992
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