TY - JOUR AU - R. G. Shterenberg TI - Absolute continuity of spectra of two-dimensional periodic Schr\"odinger operators with positive electric potentials JO - Algebra i analiz PY - 2001 SP - 196 EP - 228 VL - 13 IS - 4 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/AA_2001_13_4_a9/ LA - ru ID - AA_2001_13_4_a9 ER -