Upplýsingar frá listasamtökum (staðfest af Operabase)
Die Zwingburg by Krenek, The Secret Kingdom by Krenek, sun 07 mar 1999, Frá (1999/1999), Leikstýrt af Michael Scheidl,, Hljómsveitarstjóri Matthias Fletzberger, Jugendstiltheater am Steinhof, Vienna, Austria