Hicks, John R., author
The Clarendon Press, 1952
Buku Teks
Becker, William E., author
Prentice-Hall, 1971
Buku Teks
Hicks, John R., author
Oxford University Press, 1975
Buku Teks
Lipsey, Richard G., 1928-, author
Weidenfeld and Nicolson, 1972
Buku Teks
McEachern, William A., author
South-Western College Publishing, 1988
Buku Teks