Bergman, J., Greenston, P. and Healy, R. (1972) The agglomeration process in urban growth. UrbanStudies, Vol. 9, No. 3.
2.
Chen, A.H.Y., Jen, F.C. and Zionts, S. (1971) The optimal portfolio revision policy. The Journal of Business, Vol. 44, No. 1: 51-62.
3.
Markowitz, H. (1954) Portfolio Selection: Efficient Diversification of Investments. New York: John Wiley and Sons.
4.
National Resources Planning Board (1943) Industrial Location and National Resources. Washington, D.C.
5.
Thompson, W.R. (1968) Internal and external factors in the development of urban economies. In Perloff, H. S. and Wingo, L. (eds.), Issues in Urban Economics. Baltimore: The Johns Hopkins Press.