D. A, C., and M. I. “UN PROBLEME DE COQUES ELASTIQUES MINCES AVEC PROBLEME LIMITE A ENERGIE NON BORNEE”. Annals of Science and Technology, Vol. 1, no. 2, Feb. 2007, p. 7, https://journals.univ-ouargla.dz/index.php/AST/article/view/206.