COHEN, D. (1975) "The Value of Social Experiments," pp. 147-175 in A. Rivlin and P. Timpane (eds.) Planned Variation in Education. Washington, DC: The Brookings Institution.
2.
LANOUE, G. (1972) "Vouchers: The End of Public Education?" pp. 128-145 in G. La Noue (ed.) Educational Vouchers: Concepts and Controversies. New York: Teachers College Press.
