Behaviour of material in alteration of loading and stress-relaxationKenk, KaljuProceedings of the 18th International Conference "Boundary & Finite Elements Methods in Mechanics of Solids & Structures" : St.-Petersburg, May 2000. Vol. 22000 / p. 275-281 Minimum weight problem of circular plates subjected to dynamic loading, considering the non-linear hardening of materialKirs, JüriProceedings of the 18th International Conference "Boundary & Finite Elements Methods in Mechanics of Solids & Structures" : St.-Petersburg, May 2000. Vol. 22000 / p. 281-289