@article{NSJOM_2003_33_1a_7,
     author = {Z. Walczak},
     title = {On modified 

 {Szasz-Mirakyan} operators},
     journal = {Novi Sad Journal of Mathematics},
     pages = {93-107},
     year = {2003},
     volume = {33},
     number = {1},
     url = {http://geodesic.mathdoc.fr/item/NSJOM_2003_33_1a_7/}
}