Drucker, D. C. and Prager, W. (1952). “Soil mechanics and plastic analysis for limit
design.” Quarterly of Applied Mathematics, Vol. 10, No. 2, pp. 157-165.Drucker, D.
C. and Prager, W. (1952). “Soil mechanics and plastic analysis for limit design.”
Quarterly of Applied Mathematics, Vol. 10, No. 2, pp. 157-165.