Wachtel, Paul L.
The Free Press, 1983
Buku Teks
Drucker, Peter F. (Peter Ferdinand), 1909-2005, author
Harper & Brothers, 1957
Buku Teks
Sage Publications, 1982
Buku Teks
Joskow, Paul L.
MIT Press, 1981
Buku Teks
Macrae, Norman.
Macmillan, 1984
Buku Teks