@article{PIM2_1989__45(59)_257849,
     author = {Agrawal, P.N. and Gupta, Vijay and Sahai, A.},
     title = {On convergence of derivatives of linear combinations of modified {Lupas} operators.},
     journal = {Publications de l 'Institut Math\'ematique. Nouvelle S\'erie},
     pages = {95},
     publisher = {mathdoc},
     volume = {45(59)},
     year = {1989},
     zbl = {0677.41019},
     language = {en},
     url = {https://geodesic-test.mathdoc.fr/item/PIM2_1989__45(59)_257849/}
}