@article{RSMUP_2004__112__199_0,
     author = {Ernst, Thomas},
     title = {Some results for $q$-functions of many variables},
     journal = {Rendiconti del Seminario Matematico della Universit\`a di Padova},
     pages = {199--235},
     publisher = {Seminario Matematico of the University of Padua},
     volume = {112},
     year = {2004},
     mrnumber = {2109962},
     zbl = {1167.33308},
     language = {en},
     url = {http://www.numdam.org/item/RSMUP_2004__112__199_0/}
}