Herbert, Theodore T., author
Macmillan, 1976
Buku Teks
Steers, Richard M., compiler
McGraw-Hill , 1983
Buku Teks
Luthans, Fred, author
McGraw-Hill, 1981
Buku Teks
Brickey, Kathleen F., author
Litt;e, Brown, 1995
Buku Teks
Allyn and Bacon, Inc., 1975
Buku Teks