For citations:

Sorokina M.V., Morshchinkina Y.V. Invariant almost contact structure on the real extension of a sphere. Uchenye Zapiski Kazanskogo Universiteta. Seriya Fiziko-Matematicheskie Nauki. 2025;167(1):140-149. (In Russ.) https://doi.org/10.26907/2541-7746.2025.1.140-149