Edell, Ron
Kensington publishing Corp., 1983
Buku Teks
Tambunan, Emil H., author
Indonesia Publishing House, 2009
Buku Teks
Wheat, Dale, author
Springer, 2012
eBooks
Brunner-Routledge, 2003
Buku Teks
Shaffer, Rick, author
Lowell House, 1999
Buku Referensi