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Edward Elgar, 2012
Buku Teks
Nickels, William G.,
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Buku Teks
Andrews, P.W.S., author
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Buku Teks
Hornby, Win, author
Prentice-Hall, 2001
Buku Teks
Nickels, William G., author
McGraw-Hill, 2008
Buku Teks