Benham, Frederic
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Buku Teks
Lutz, Vera
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Buku Teks
Case, Karl E.
Pearson, Prentice Hall, 2009
Buku Teks
Mankiw, N. Gregory
Harcout College, 1998
Buku Teks
Case, Karl E.
Prentice-Hall, 2004
Buku Teks