@article{KJM_2022_46_1_a11,
     author = {Vijay Gupta and Gancho Tachev},
     title = {Some {Results} on {Post-Widder} {Operators} {Preserving} {Test} {Function} $x^r$},
     journal = {Kragujevac Journal of Mathematics},
     pages = {149 },
     publisher = {mathdoc},
     volume = {46},
     number = {1},
     year = {2022},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/KJM_2022_46_1_a11/}
}