1.Nicomedes WL, Bathe K-J, Moreira FJS, Mesquita RC. The method of finite spheres in acoustic wave propagation through nonhomogeneous media: Inf-sup stability conditions. Vietnam J. Mech. [Internet]. 2020 Sep. 27 [cited 2025 Nov. 8];42(3):209-37. Available from: https://vjmech.vast.vn/vjmech/article/view/15336