@article{NSJOM_1976_6_Nonea_1,
     author = {Pap Endre},
     title = {n-convex 

 functions on a semigroup with a root function},
     journal = {Novi Sad Journal of Mathematics},
     pages = {7-13},
     publisher = {mathdoc},
     volume = {6},
     year = {1976},
     url = {http://geodesic.mathdoc.fr/item/NSJOM_1976_6_Nonea_1/}
}