Gillespie, Cecil
Prentice-Hall, 1971
Buku Teks
Johnson, Eldred A.
McGraw-Hill, 1959
Buku Teks
Page, John R., 1949-
Prentice-Hall, 1987
Buku Teks
Hall, James A.
South-Western College , 2001
Buku Teks
Mehta, Nitin H., 1946-
Prentice-Hall, 1977
Buku Teks