1. Massonnet C. andSave M.,Calcul plastique des constructions, A.S.B.L., Bruxelles, 1961.
2. Gross O. andPrager W.,Minum-weight design for moving loads, Prof. 4th U.S. Nat. Congr. Appl. Mech., 2, 1047, ASCE, New York, 1962.
3. Dantzig G. B.,Linear programming and extensions, Princeton University Press, Princeton, USA, 1963.
4. Shield R. T.,Optimum design method for multiple loading, J. Appl. Math. Phys. (ZAMP), 14, 38–45, 1963.
5. Save M. A. andPrager W.,Minimum-weight design of beams subjected to fixed and moving loads, J. Mech. Phys. Solids, 11, 255–267, 1963.