Catalogued in RISM as “Fürwahr diese Glut (Excerpts); Manuscript copy; A-Wn Mus. Hs. 37067” by Anonymus. RISM 600500479
Probable
A German version: the duet 'Fürwahr diese Glut' (incipits 1.1.1, 1.1.2) has the music, with different words, of no. 7, the duet 'Jarni son minois est charmant' (incipits 1.1.3, 1.1.1), in an arrangement from Les Troqueurs; the German part is also numbered 7. RISM's heading on that copy is François-Joseph Hérold, but its title reads 'Paroles de M. Dartois. Musique de F. Herold', sung by Mme Lemonnier and M. Paul: Ferdinand Hérold's opera of 1819, not Dauvergne's earlier one. The matches are short.
Attributed copies compared (2 of 2 encoded incipits match):
1.1.1 Duett Nr.7. Moderato · vl 1 · 7 of 7 pitches agree
{'8GxA}{BFGE}/4xC--/{8GxABFGE}/4xC--/{8''E'AAA}{8.6''D'F}/8G-4--/8G-G-4F/1.1.2 · T · “Fürwahr diese Glut” · 6 of 6 pitches agree
=2/4--8-,D/4G-8.B6A/8G-4.G8F/=2/4--8-D/4G-8.B6A/8G-4.G8F/4E-8-F/Catalogue data and incipits come from RISM (Répertoire International des Sources Musicales), CC BY 4.0. Incipits are rendered with Verovio. Source and data: https://github.com/aaymeloglu/rism-attributions.