Operators and Matrices · Volume 13, Issue 4 Abstract Korovkin theory for double sequences via power series method in modular spaces 13-71 Pages 1023-1034 DOI 10.7153/oam-2019-13-71 Downloads Short PDF Full PDF PNG Authors Fadime Dirik Sevda Yıldız Kamil Demirci Keywords power series method double sequence abstract Korovkin theorem Subject classes 40G10 41A36 46E30