@article{10_4153_CJM_2010_080_0,
     author = {Ismail, Mourad E. H. and Obermaier, Josef},
     title = {Characterizations of {Continuous} and {Discrete} {q-Ultraspherical} {Polynomials}},
     journal = {Canadian journal of mathematics},
     pages = {181--199},
     year = {2011},
     volume = {63},
     number = {1},
     doi = {10.4153/CJM-2010-080-0},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-2010-080-0/}
}