Siebert, Eleanor D., author
McGraw-Hill, 1982
Buku Teks
by Robert W. Parry ... [and others]
Prentice-Hall, 1970
Buku Teks
Murphy, Daniel B., author
Ronald Press, 1980
Buku Teks
Murphy, Daniel B., author
Ronald Press, 1969
Buku Teks
Hein, Morris, author
Brooks, 1984
Buku Teks