1. C. Berge: Espaces topologiques, fonctions multivoques, Paris 1959.
2. G. Debreu: Theory of value, New York 1959.
3. G. Debreu: New concepts and techniques in equilibrium analysis, International Economic Review,3 (1962).
4. H. G. Eggleston: Convexity, Cambridge 1958.
5. J. C. Milleron: Duality in consumer behavior analysis. Paris: Institut National de la Statistique et des Etudes Economiques. (Paper presented at the European Meeting on Statistics, Econometrics and Management Science, Amsterdam 1968.)