Bibliographical references BOWLEY, A.L. (1924): "The Mathematical Groundwork of Economics". Reprint of Economic Classics. Augustus M. Kelley, Bookseller. New York, 1965. BRANDER, J.A. y SPENCER, B.J. (1985): "Export Subsidies and International Market Share Rivalry". Journal of International Economics, 18, pp. 83-100. BRESNAHAN, T.H. (1981): "Duopoly Models with Consistent Conjectures". The American Economic Review, Vol 71, No. 5. December, 1981. CABRAL, L.M.B. (1992): "Conjectural Variations as a Reduced Form". VIII Jornadas de Economía Industrial. Madrid, Septiembre 1992. CLARKE, R. (1985): "Industrial Economics". Basil Blackwell. Cambridge, Massachusetts. Reprint 1990. CLARKE, R. & DAVIES, S.W. (1982): "Market Structure and Price-Cost Margins". Economica, 49, pp. 277-87. CHENG, L. (1985): "Comparing Bertrand and Cournot Equilibria: A geometric approach". Rand Journal of Economics. Vol 16, Nº 1. Spring 1985. EATON, J. & GROSSMAN, G.M. (1986): "Optimal Trade and Industrial Policy under Oligopoly". Quarterly Journal of Economics 101, pp. 383-406. EMERSON, M. et Al. (1988): "The Economics of 1992". European Economy, Nº 35. FRIEDMAN, J. (1986): "Game Theory with Applications to Economics". Oxford University Press. New York. FRIEDMAN, J. (1988): "On the strategic importance of prices versis quantities". Rand Journal of Economics, Vol 19, Nº 4. Winter 1988. GALBRAITH, J.K. (1983): "La Anatomía del Poder". Edición Española. Plaza y Janes Editores S.A. Barcelona. HELPMAN, E. & KRUGMAN, P.R. (1989): "Trade Policy and Market Structure". The MIT Press. Cambridge. Massachusetts. KAMIEN, M.I. & SCHWARTZ, N.L. (1983): "Conjectural Variations". Canadian Journal of Economics. May 1983. KREPS, D.M. (1990) "A Course in Microeconomic Theory". Harvester Wheatsheaf. New York, 1990. LAITNER, J. (1980): ""Rational" Duopoly Equilibria". The Quarterly Journal of Economics. December 1980. PERRY, M.K. (1982): "Oligopoly and Consistent Conjectural Variations". Bell Journal of Economics 13, pp. 197-205. SCHMALENSEE, R. (1987): "Collusion versus differenciatad efficiency: testing alternative hypothesis". Journal of Industrial Economics, Vol 35, No 4. June 1987. SCHMALENSEE, R. & WILLIG, R.D. (eds.) (1989): "Handbook of Industrial Organization". Vols I y II. Elsevier Science Publisher B. V. North-Holland. Amsterdam. SEGURA, J. (1993): "Teoría de la Economía Industrial". Editorial Civitas, S.A. Madrid. SUTTON, J. (1991): "Sunk Costs and Market Structure". The MIT Press. Cambridge. Massachusets. TIROLE, J. (1988): "The Theory of Industrial Organisation". The MIT Press. Cambridge, Massachusetts.