TY - JOUR AU - V. I. Vozyakov TI - Approximate second quantization method in the theory of quantum crystals JO - Teoretičeskaâ i matematičeskaâ fizika PY - 1977 SP - 136 EP - 144 VL - 33 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/TMF_1977_33_1_a11/ LA - ru ID - TMF_1977_33_1_a11 ER -