Ubaldo is a German tragedy in five acts by August von Kotzebue (1761-1819)[1].
Published as Ubaldo: ein Trauerspiel in fünf Akten by Kummer, Leipzig, 1808
Translated into Dutch as Ubaldo by J S van Esveldt Holtrop.
Facsimile version of the German text, Google E-book [2]
