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Hooker, M. B., author
Oxford University Press, 1976
Buku Teks
Collier, John G. (John Greenwood), author
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Buku Teks
Henn, Harry, Alexander, John R
St.Paul,Minn : West publishing Co, 1983,
Buku Referensi
edited by Naoyuki Sakumoto, Hikmahanto Juwana
Institute of Developing Economies Japan External Trade Organization, 2007
Buku Teks