The New Encyclopaedia Britannica : volume 7
Encyclopaedia Britannica Inc., 1983
 Buku Referensi
The New Encyclopaedia Britannica : volume 7
Encyclopaedia Britannica Inc., 1983
 Buku Referensi
The New Encyclopaedia Britannica : volume 7
Encyclopaedia Britannica Inc., 2003
 Buku Referensi
The New Encyclopaedia Britannica : volume 7
Encyclopaedia Britannica Inc., 1978
 Buku Referensi
The New Encyclopaedia Britannica : volume 7, micropaedia ready reference
Encyclopaedia Britannica Inc., 1998
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