Duronio, Margaret A.
Jossey - Bass Publishers , 1991
Buku Teks
Harris, Seymour E.
McGraw-Hill Book Company, Inc., 1962
Buku Teks
Kramer, Martin, author
The Carnegie Foundation , 1980
Buku Teks
Veblen, Thorstein
Hill and Wang , 1965
Buku Teks
Apps, Jerold W., author
Jossey-Bass , 1988
Buku Teks