TY - JOUR AU - H. Eliopoulos TI - Some properties of differentiable structures defined by nilpotent operators of degree r JO - Δελτίο της Ελληνικής Μαθηματικής Εταιρίας PY - 1966 SP - 81 EP - 94 VL - 07 IS - A UR - http://geodesic.mathdoc.fr/item/DEME_1966_07_A_a6/ LA - gr ID - DEME_1966_07_A_a6 ER -