1. Application of a version of the Rayleigh technique to problems of beams, columns, membranes and plates;Bert,1986
2. Optimization of eigenvalues when using the Galerkin method;Laura;American Institute of Chemical Engineering Journal,1986
3. The finite element method and the variational calculus in the analysis of vibrating rods;Utjes;Instituto Balseiro, San Carlos de Bariloche, Argentina, Special Report,1982