For citations:

Smirnov Yu.G., Martynova V.Yu. A modified method of variable separation for the problem of TE wave diffraction on a diffraction grating with two-layer lines in the period. Uchenye Zapiski Kazanskogo Universiteta. Seriya Fiziko-Matematicheskie Nauki. 2025;167(3):531-546. (In Russ.) https://doi.org/10.26907/2541-7746.2025.3.531-546