Manktelow, K.I., author
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Buku Teks
Hurley, Patrick J., 1883-1963, author
Wadsworth and Cengage Learning, 2012
Buku Teks
Hurley, Patrick J., 1883-1963, author
Wardsworth Cengage Learning, 2012
Buku Teks
Copi, Irving M., author
Macmillan, 1961
Buku Teks
Copi, Irving M., author
Prentice-Hall, 1995
Buku Teks