TY - JOUR AU - Grigorios Tsagas TI - On the Surfaces Whose Normal Bundles Have Special Properties JO - Ευκλείδης Γ PY - 1987 SP - 59 EP - 67 VL - 15 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/EUG_1987__15_a15/ LA - gr ID - EUG_1987__15_a15 ER -