Catalogued in RISM as “La schiava (Excerpts, Arrangement); Manuscript copy; US-SFsc *M2.5 v. 45” by Anonymus. RISM 117437
Same music
Matches the Sinfonia of Guglielmi's Il ratto della sposa (three copies, two naming Guglielmi), rhythm included; here captioned 'Overture in La Schiava'. One Guglielmi copy notes the sinfonia also circulated, wrongly, as Sacchini's.
Attributed copies compared (1 of 1 encoded incipit match):
1.1.1 · cemb · 19 of 19 pitches agree
''4G8-{6BtA}4G8-{6BA}/4G8-{6B'''C}4D8-{''6B'''C}/!{8D''6B'''C}!f/8D4''G^'B^D8-6{''BA}4G8-{6BA}/4G^'B^D8-{6''B'''C}4D8-{6''B'''C}/{866D''B'''C}{D''B'''C}{8D''BGD}/also RISM 706000009 1.1.1 [Sinfonia]. Allegro assai
also RISM 850002132 1.1.1 Allegro assai
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.