Le Sourne, H. ., C. . Wielgosz, and C. . Duforet. “Developpement d’elements Continus De Coques Axisymetriques Et De Coudes”. European Journal of Computational Mechanics, vol. 8, no. 3, Mar. 1999, pp. 273-98, https://journals.riverpublishers.com/index.php/EJCM/article/view/3013.