Anton, Hector R., author
Houghton Mifflin, 1978
Buku Teks
Heitger, Lester E.
Ohio. South-Western Publishing Co., 1992
Buku Teks
Eldenburg, Leslie G.
Wiley India, 2007
Buku Teks
Eka Pratiwi, author
Program Pascasarjana Universitas Indonesia, 2012
UI - Tesis (Open)
Shillinglaw, Gordon, author
Richard D. Irwin, 1982
Buku Teks