%0 Journal Article %A May, C. P. %T Saturation and Inverse Theorems for Combinations of a Class of Exponential-Type Operators %J Canadian journal of mathematics %D 1976 %P 1224-1250 %V 28 %N 6 %U http://geodesic.mathdoc.fr/articles/10.4153/CJM-1976-123-8/ %R 10.4153/CJM-1976-123-8 %F 10_4153_CJM_1976_123_8