TY - JOUR AU - D. Bättig TI - A toroidal compactification of the Fermi surface for the discrete Schrödinger operator. JO - Commentarii mathematici Helvetici PY - 1992 SP - 1 EP - 16 VL - 67 IS - 3 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/CMH_1992__67_3_140254/ ID - CMH_1992__67_3_140254 ER -