The Blackwell encyclopaedia of political science
edited by Vernon Bogdanor
Blackwell Reference, 1991
 Buku Referensi
International encyclopedia of government and politics : volume 1
editor Frank N. Magill
Toppan Company, 1996
 Buku Referensi
International encyclopedia of government and politics : volume 2
editor Frank N. Magill
Toppan Company, 1996
 Buku Referensi
Encyclopedia of government and politics : volume 1
edited by Mary Hawkesworth, Maurice Kogan
Routledge, 1992
 Buku Referensi
Encyclopedia of government and politics: volume 2
editor, Mary Hawkesworth, Maurice Kogan
Routledge, 1992
 Buku Referensi