The New Encyclopaedia Britannica : volume 24
Encyclopaedia Britannica Inc., 2003
 Buku Referensi
The New Encyclopaedia Britannica : volume 24
Encyclopaedia Britannica Inc., 1988
 Buku Referensi
The New Encyclopaedia Britannica : volume 24, micropaedia konowledge in depth
Encyclopaedia Britannica Inc., 2002
 Buku Referensi
The New encyclopaedia Britannica : volume 24, macropaedia knowledge in depth
Encyclopaedia Britannica Inc., 1998
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Everyman's encyclopaedia : volume one
edited by E. F. Bozman
J. M. Dent & Sons, 1958
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