TY - JOUR AU - Tuomas Sorvali TI - The boundary mapping induced by an isomorphism of covering groups JO - Annales Fennici Mathematici PY - 1973 VL - 521-560 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.5186/aasfm.1973.526/ DO - 10.5186/aasfm.1973.526 LA - en ID - AFM_1973_521-560_a34 ER -