edited by Timothy D.J. Chappell
Edinburgh University, 1997
Buku Teks
Rachels, James, 1941-2003, author
McGraw-Hill , 2012
Buku Teks
Shipka, Thomas A., author
McGraw-Hill, 1996
Buku Teks
Hutcheson, Francis, author
Cambridge University Press, 2014
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