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Routledge, 2008
Buku Teks
Betsky, Aaron, author
Gingko Press, 2000
Buku Teks
Jonathan Hill
Routledge, 2001
Buku Teks
Bovet, Daniel Piere, author
Prentice-Hall, 1994
Buku Teks
Brolin, Brent C., author
Van Nostrand Reinhold, 1976
Buku Teks