World press encyclopedia; volume II
edited by George Thomas Kurian
Facts on File, 1982
 Buku Referensi
The World book encyclopedia : volume 9, I
Field Enterprises Educational Corporation, 1963
 Buku Referensi
The encyclopedia of democracy : volume I
editor in chief, Seymour Martin Lipset
Routledge, 1995
 Buku Referensi
The Columbia encyclopedia; Volume I
edited by William Bridgwater dan Seymour Kurtz
Columbia University Press, 1963
 Buku Referensi
Encyclopedia of world cultures: volume IV
editor, Linda A. Bennett
New York G.K. Hall [and] Company 1991-1996
 Buku Referensi