Michael Leccese
McGraw-Hill, 2000
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by United Nations
United Nations, [Date of publication not identified]
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Woon, Walter C.M.
NUS Press (National University of Singapore), 2016
Buku Teks
Jurnal Kajian Wilayah Eropa Vol. 3 No. 2 2007: 83-105, 2007
Artikel Jurnal
Goodrich, Leland M.
Stevens & Sons, 1949
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