%0 Journal Article %A Elena Prestini %T Operators of Bochner-Riesz type for the helix %J Studia Mathematica %D 1984 %P 7-16 %V 79 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/sm-79-1-7-16/ %R 10.4064/sm-79-1-7-16 %G de %F 10_4064_sm_79_1_7_16