@article{BUMI_1962_3_17_2_a1,
     author = {Gupta, D. P.},
     title = {Sur l'approximation de la fonction par les moyennes arithm\'etiques de  sa s\'erie ultrasph\'erique.},
     journal = {Bollettino della Unione matematica italiana},
     pages = {166--171},
     publisher = {mathdoc},
     volume = {Ser. 3, 17},
     number = {2},
     year = {1962},
     zbl = {0118.29202},
     mrnumber = {142962},
     url = {http://geodesic.mathdoc.fr/item/BUMI_1962_3_17_2_a1/}
}