Frommer, Herbert H., author
Mosby, 2011
Buku Teks
Francis Peter S.J.
Tata McGraw-Hill, 2012
Buku Teks
Regula H. Robnett , Walter C. Chop, edited
Jones and Bartlett Learning, 2015
Buku Teks
Howard Tumber, editor
Routledge, 2000
Buku Teks
Artikel Jurnal