@article{01560852, title = {Efficiency in terms of Lagrangian.}, journal = {APPS. Applied Sciences}, volume = {3}, year = {2001}, pages = {11-19}, zbl = {1033.90114}, language = {en}, url = {http://dml.mathdoc.fr/item/01560852} }
Bebu, I.; Ureche, G. Efficiency in terms of Lagrangian.. APPS. Applied Sciences, Tome 3 (2001) pp. 11-19. http://gdmltest.u-ga.fr/item/01560852/