@article{MOMA_1981__91_178015,
     author = {R.K.S. Rathore and O.P. Singh},
     title = {Limits of {Certain} {Iterates} of {Post-Widder} {Operators.}},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {131--138},
     publisher = {mathdoc},
     volume = {91},
     year = {1981},
     zbl = {0448.47018},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1981__91_178015/}
}