Manning, Peter J., author
Oxford University Press, 1990
Buku Teks
by Taylor, Barbara... [et al.]
McGraw-Hill, 1995
Buku Teks
Spears, Deanne Milan, author
McGraw-Hill, 2000
Buku Teks
Crawley, Sharon J., author
McGraw-Hil, 2000
Buku Teks
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Buku Referensi