An allem ist Hütchen schuld!
... that when Siegfried Wagner wrote the libretto for his opera An allem ist Hütchen schuld!, he used themes from many fairy tales?
... that when <a href="./Siegfried_Wagner" id="mwAnw" rel="mw:WikiLink" title="Siegfried Wagner">Siegfried Wagner</a> wrote the libretto for his opera <i id="mwAn0"><b id="mwAn4"><a href="./An_allem_ist_Hütchen_schuld!" id="mwAn8" rel="mw:WikiLink" title="An allem ist Hütchen schuld!">An allem ist Hütchen schuld!</a></b></i>, he used themes from many fairy tales?