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Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2004
UI - Tesis (Membership)
Hamblen, David L., author
Churchill Livingstone, Elsevier, 2007
Buku Teks
Adams, George P.
Thomas Y. Crowell Company, 1955
Buku Teks
McNelly, A.E.
Prentice-Hall, 1958
Buku Teks
Maegraith, B.G., author
The English Language Book Society, 1971
Buku Teks