@article{hahn:1949:opd,
    author = {Hahn, Wolfgang},
     title = {\"{U}ber {O}rthogonalpolynome, die
              $q$-{D}iff\-er\-enzen\-gleich\-ungen gen\"ugen},
   journal = {Math. Nachr.},
    volume = {2},
      year = {1949},
     pages = {4–34},
  language = {German},
   mrclass = {41.1X},
  mrnumber = {MR0030647 (11,29b)},
mrreviewer = {N. J. Fine},
     zblno = {0031.39001}}