edited by Brian Harvey, Henk van Luijk and Horst Steinmann
Prentice-Hall, 1994
Buku Teks
Bearden, James H., author
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Buku Teks
Griffin, Ricky W., author
Addison-Wesley, 1995
Buku Teks
Orsini, Philip S.
Gramedia Pustaka Utama, 1996
Buku Teks
The World Bank, 2007
Buku Teks