The New Encyclopaedia Britannica : volume 6, micropaedia ready reference
Encyclopaedia Britannica Inc., 2002
 Buku Referensi
The New Encyclopaedia Britannica : volume 4, micropaedia ready reference
Encyclopaedia Britannica Inc., 1988
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The New Encyclopaedia Britannica : volume 2, micropaedia ready reference
Encyclopaedia Britannica Inc., 1998
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The New Encyclopaedia Britannica : volume 10, micropaedia ready reference
Encyclopaedia Britannica Inc., 1998
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The New Encyclopaedia Britannica : volume 1, micropaedia ready reference
Encyclopaedia Britannica Inc., 2002
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