@article{NSJOM_2003_33_1a_8,
     author = {Lj. 

 Petkovi\'c and M. Petkovi\'c and D. \v{Z}ivkovi\'c},
     title = {Hansen-Ptrick's 

 family is of {Laguerre's} type},
     journal = {Novi Sad Journal of Mathematics},
     pages = {109-115},
     year = {2003},
     volume = {33},
     number = {1},
     url = {http://geodesic.mathdoc.fr/item/NSJOM_2003_33_1a_8/}
}