The New Encyclopaedia Britannica : volume 14
Encyclopaedia Britannica Inc., 1978
 Buku Referensi
The New Encyclopaedia Britannica : volume 14
Encyclopaedia Britannica Inc., 1988
 Buku Referensi
The New Encyclopaedia Britannica : volume 14, micropaedia konowledge in depth
Encyclopaedia Britannica Inc., 2002
 Buku Referensi
The New Encyclopaedia Britannica : volume 14, macropaedia knowledge in depth
Encyclopaedia Britannica Inc., 1998
 Buku Referensi
Encyclopaedia Britannica : volume 14
Encyclopaedia Britannica Inc., 1967
 Buku Referensi