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W.H. Freeman, 1970
Buku Teks
Routledge, 2018
Buku Teks
Houghton, John Theodore
Cambridge University Press, 1986
Buku Teks
Tiara Deysha Rianti
Universitas Indonesia, 2014
UI - Skripsi (Membership)
Kolb, David A.
Prentice-Hall, 1991
Buku Teks