Petrov, E., & Havrylenko, I. (2023). Stability of minimal surfaces in the sub-Riemannian manifold $\widetilde{E(2)}$. Visnyk of V. N. Karazin Kharkiv National University. Ser. Mathematics, Applied Mathematics and Mechanics, 98, 50-67. https://doi.org/10.26565/2221-5646-2023-98-04