The World book encyclopedia : volume 22
World Book, 1984
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The World book encyclopedia : volume 23
World Book, 1985
 Buku Referensi
The World book encyclopedia : volume 24
World Book, 1985
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Concise earth book : world atlas
James E Davis, colsultan
Graphic Learning,, 1978
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The book of the world / Kartographisches Institut Bertelsmann
Macmillan, 1995
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