Culbertson, John M., editor
McGraw-Hill, 1972
Buku Teks
Kamerschen, David R.
South-Western Publishing, 1992
Buku Teks
Chandler, Lester Vernon, 1905-
Harper & Row , 1959-1973
Buku Teks
Auerbach, Robert D.
Macmillan, 1989
Buku Teks
Miller, Roger LeRoy
McGrow-Hill, 1985
Buku Teks