1. Baumol, W. J.,Economic Theory and Operations Analysis, Prentice-Hall, Englewood Cliffs, New Jersey, 1961, Chapter 18.
2. Chamberlin, E.,The Theory of Monopolistic Competition, Harvard University Press, Cambridge, Mass., 1937, Appendix C.
3. Dorfman, R., P. A. Samuelson, and R. M. Solow,Liniar Programming and Economic Analysis, McGraw-Hill, New York, 1958, pp. 427–8.
4. Hotelling, H., “Stability in Competition,” in G. J. Stigler and K. E. Boulding (eds.),Readings in Price Theory, Richard D. Irwin, Chicago, 1952, pp. 467–484.
5. Isard, W.,Location and Space-Economy, John Wiley & Sons, New York, 1956, pp. 158–165.