1.
Burskii VP, ShtepinaТV. On the Spectrum of an Equivariant Extension of the Laplace Operator in a Ball. Ukr. Mat. Zhurn. [Internet]. 2000Nov.25 [cited 2024Jul.22];52(11):1473-8. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/4554