TY - JOUR AU - Giambruno, A. TI - On the Symmetric Hypercenter of a Ring JO - Canadian journal of mathematics PY - 1984 SP - 421 EP - 435 VL - 36 IS - 3 UR - http://geodesic.mathdoc.fr/articles/10.4153/CJM-1984-026-2/ DO - 10.4153/CJM-1984-026-2 ID - 10_4153_CJM_1984_026_2 ER -