Jones, Garth N.
Routledge & Kegan Paul, 1968
Buku Teks
Thompson, Victor A., author
Alfred A. Knopf, 1969
Buku Teks
Caplo, Theodore, author
Harcourt, Brace & World, 1964
Buku Teks
Beneficial Management Institute, [Date of publication not identified]
Buku Teks
French, Wendell L., author
Prentice-Hall International, 1990
Buku Teks