1. Becker, G. S. (1975). Human Capital: A Theoretical and Empirical Analysis, with Special Reference to Education. 2nd ed. New York: National Bureau of Economic Research.
2. Bowen, H. R. (1977). Investment in Learning: The Individual and Social Value of American Higher Education. San Francisco: Jossey-Bass.
3. Bowen, H. R. (1980). The Costs of Higher Education: How Much Do Colleges and Universities Spend per Student and How Much Should They Spend? San Francisco: Jossey-Bass Publishers.
4. Brinkman, P. T. (1986). ?Marginal costs?, mimeograph. Boulder: NCHEMS.
5. Carnegie Commission. (1973). Higher Education: Who Pays? Who Benefits? Who Should Pay? Hightstown, New Jersey: McGraw-Hill Book Company.