%0 Journal Article %A Furuta, Takayuki %T Essentially Convexoid Operators %J Canadian journal of mathematics %D 1981 %P 257-274 %V 33 %N 2 %U http://geodesic.mathdoc.fr/articles/10.4153/CJM-1981-021-x/ %R 10.4153/CJM-1981-021-x %F 10_4153_CJM_1981_021_x