TY - JOUR AU - Alexei V. Penskoi TI - Isoperimetric Inequalities for Higher Eigenvalues of the Laplace--Beltrami Operator on Surfaces JO - Informatics and Automation PY - 2019 SP - 291 EP - 308 VL - 305 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/TRSPY_2019_305_a15/ LA - ru ID - TRSPY_2019_305_a15 ER -