Prentice-Hall, 2000
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Marantika, Bram
Universitas Indonesia, 2003
UI - Skripsi (Membership)
Haspeslagh, Philippe C.
N.Y. The Free Press, 1991
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Bob Hamlin, Jane Keep, Ken Ash
Prentice-Hall, 2001
Buku Teks
Bean, Roger
AMACOM, 2002
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