Karaprtyan, G. A., & Darbinyan, A. A. (2023). NOETHERICITY OF SEMI-ELLIPTICAL OPERATOR WITH CONSTANT COEFFICIENTS IN THE RANGE. Proceedings of the YSU A: Physical and Mathematical Sciences, 42(3 (217), 16–24. https://doi.org/10.46991/PYSU:A/2008.42.3.016