Office of International Information Programs, 1991
Buku Teks SO
United State Information Agency, 1994
Buku Teks SO
Patrick, John
Macmillan Publishing Company, 1984
Buku Teks SO
Quint, Howard H
Dorsey Press, 1968
Buku Teks
Muccigrosso
Krieger publishing company, 2001
Buku Teks