Clinard, Marshall B. (Marshall Barron), author
Sage Publications, 1985
Buku Teks
Owens, Richard N.
Homewood, Ill. Richard D. Irwin, Inc , 1958
Buku Teks
Drucker, Peter F. (Peter Ferdinand), 1909-2005, author
Pan Books, 1982
Buku Teks
Drucker, Peter F. (Peter Ferdinand), 1909-2005, author
Harper & Row, 1945
Buku Teks
Frohman, Alan L., author
McGraw-Hill, 1992
Buku Teks