@article{kneser:1948:ral,
    author = {Kneser, Hellmuth},
     title = {Reelle analytische {L}\"osungen der {G}leichung
              {$\varphi(\varphi(x))=e\sp x$} und verwandter
              {F}unktionalgleichungen},
   journal = {J. Reine Angew. Math.},
  fjournal = {Journal f\"ur die Reine und Angewandte Mathematik},
    volume = {187},
      year = {1950},
     pages = {56–67},
      issn = {0075-4102},
   mrclass = {39.0X},
  mrnumber = {MR0035385 (11,726e)},
mrreviewer = {G. Valiron},
     zblno = {0035.04801}}