Cochrane, James C.
David & Charles , 2008
Buku Teks
Ziegler, Kathleen
Rockport Publishers, 1994
Buku Referensi
Shannon, Faith
Reed International Books, 1987
Buku Referensi
Lafosse, Michael G.
Quarry Books, 1998
Buku Referensi
Universitas Indonesia, 1987
UI - Tugas Akhir