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Buku Teks
De Blij, Harm J., author
John Wiley & Sons, 19880
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De Blij, Harm J., author
John Wiley & Sons, 1981
Buku Teks
Martin, A.W.
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Buku Teks
Faculty of Geography, Gadjah Mada University, 1998
Majalah, Jurnal, Buletin