Atkinson, Lloyd C., author
Richard D. Irwin, 1982
Buku Teks
Jones, J. Harry, author
Pitman, 1935
Buku Teks
McKenzie, Richard B., author
McGraw-Hill, 1980
Buku Teks
Lipsey, Richard G., 1928-, author
Harper Collin, 1996
Buku Teks
Adreson, W. H. Locke, author
Prentice Hall of India, 1986
Buku Teks