Phlips, Louis, author
Cambridge University Press, 1988
Buku Teks
Robinson, Joan, author
Macmillan, 1948
Buku Teks
Lipsey, Richard G., 1928-, author
Harper Collin, 1996
Buku Teks
Adreson, W. H. Locke, author
Prentice Hall of India, 1986
Buku Teks
Samuelson, Paul A. (Paul Anthony), 1915-2009, author
McGraw-Hill, 1992
Buku Teks