Exact and approximate solutions of the spectral problems for the differential Schrödinger operator with a polynomial potential in ${\mathbb R}^{k}$, $k\ge 2$. НК [Internet]. 2018 Mar. 29 [cited 2026 Jan. 21];21(1):66-98. Available from: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/897