Reynolds, Lloyd G., author
Prentice-Hall, 1959
Buku Teks
Morgan, Chester A., author
The Dorsey Press, 1962
Buku Teks
Borjas, George J., author
McGraw-Hill, 2010
Buku Teks
Datar, B.N.
Allied , 1968
Buku Teks
Meyers, Frederick H., author
Richard D. Irwin, 1951
Buku Teks