Artikel Jurnal
David F. Ford, Rachel Muers, editor
Blackwell Publishing, 2008
Buku Teks
Doyglas J. Davies, author
Berg, 2002
Buku Teks
Rahner, Karl, author
The Crossroad Publishing Company, 1981
Buku Referensi
Descrates, Rene
J.M. Dent & Sons , 1949
Buku Teks