1. 1. J. S. Bain , Industrial Organization, 2nd ed. New York 1968.
2. 2. M. Beckmann , Location Theory. New York 1968.
3. 3. E. H. Chamberlin , The Theory of Monopolistic Competition, 6th ed. Cambridge 1950.
4. Product Differentiation and Advertising: Some Lessons from Soviet Experience;Goldman;Jour. Pol. Econ.,1960
5. Stability in Competition;Hotelling;Econ. Jour.,1929