1. Jehle, G. A., Advanced Microeconomic Theory, Prentice Hall, Englewood Cliffs, New Jersey, 1991.
2. LaFrance, J. T., and Barney, L. D., The Envelope Theorem in Dynamic Optimization, Journal of Economic Dynamics and Control, Vol. 15, pp. 355-385, 1991.
3. Caputo, M. R., The Slutsky Matrix and Homogeneity in Intertemporal Consumer Theory, Journal of Economics, Vol. 60, pp. 255-279, 1994.
4. Clegg, J. C., Calculus of Variations, Interscience, New York, New York, 1967.
5. Kamien, M. I., and Schwartz, N. L., Patent Life and R&D Rivalry, American Economic Review, Vol. 64, pp. 183-187, 1974.