Allen, Clark Lee, author
Wadsworth, 1967
Buku Teks
Dorfman, Robert, author
Prentice-Hall, 1967, c.1972
Buku Teks
Haveman, Robert H., author
John Wiley, 1970
Buku Teks
Schultz, Henry
The Univ. of Chicago Press , 1938
Buku Teks
Stigler, George J., author
Macmillan, 1957, c.1942
Buku Teks