Henderson, David, author
New Zealand Business Roundtable , 1998
Buku Teks
McKinnon, Ronald I.
The Johns Hopkins University Press , 1991
Buku Teks
Reisman, George, author
Caroline House Publishers, 1979
Buku Teks
Ringer, Robert J.
Fawcett Crest, 1980
Buku Teks
Pirie, Lain, author
Routledge, 2008
Buku Teks