1. Rozvany, G.I.N, and Mroz, Z., “Analytical Methods in Structural Optimization,” Applied Mechanics Reviews, Vol. 30, N. 11, 1 977, pp. 1461–1470.
2. Cinquini, C. and Sacchi, G., “Problems of Optimal Design for Elastic and Plastic Structures,” Journal de Mécanique Appliquée, Vol. 4, No. 1, 1980, pp. 31–59.
3. Sacchi, G., “Optimal Structural Design Problems,” Ist. Naz. Alta Matematica; Seminari su “Problemi di Frontiera Libera”, Pavia, 1 979.
4. Niordson, F. and Olhoff, N., Variational Methods in Optimization of Structures, Report No. 161, The Danish Center for Applied Mathematics and Mechanics, 1979.
5. Cinquini, C., “Variational Formulation and Numerical Methods in Optimal Design,” Optimization of Distributed Parameter Structures (Ed. E.J. Haug and J. Cea ), Sijthoff Nordhoff, Alphen ann den Rijn, Netherland, 1980.