@article{02217792, title = {On the rate of convergence of certain approximation operators.}, journal = {General Mathematics}, volume = {10}, year = {2002}, pages = {85-89}, zbl = {1073.41509}, language = {en}, url = {http://dml.mathdoc.fr/item/02217792} }
Popa, Emil C. On the rate of convergence of certain approximation operators.. General Mathematics, Tome 10 (2002) pp. 85-89. http://gdmltest.u-ga.fr/item/02217792/