The World book encyclopedia : volume 6
World Book, 1985
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The New Encyclopaedia Britannica : volume 6
Encyclopaedia Britannica Inc., 1988
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The New Encyclopaedia Britannica : volume 6
Encyclopaedia Britannica Inc., 2003
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The New Encyclopedia Britannica : volume 6
Encyclopedia Britannica, 1983
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The New Encyclopaedia Britannica : volume 6
Encyclopaedia Britannica Inc., 1978
Buku Referensi