TY - JOUR AU - B. O. Vasilevskii TI - A Sufficient Nonsingularity Condition for a Discrete Finite-Gap One-Energy Two-Dimensional Schrödinger Operator on the Quad-Graph JO - Funkcionalʹnyj analiz i ego priloženiâ PY - 2015 SP - 65 EP - 70 VL - 49 IS - 3 UR - http://geodesic.mathdoc.fr/item/FAA_2015_49_3_a5/ LA - ru ID - FAA_2015_49_3_a5 ER -