Catalogued in RISM as “Concertos–A major; Manuscript copy; GB-Lbl R.M.21.c.10-15.” by Anonymus. RISM 800247358
Same music
The one encoded movement matches a Giuseppe Sammartini concerto in the same R.M. collection note for note.
Attributed copies compared (1 of 1 encoded incipit match):
1.1.1 Allegro · vl 1 · 9 of 9 pitches agree
4''A{8.6GtF}/{8E'A}{,A''F}/4ED/''4A{8.G6F}/{8E'A},{A''F}/4ED/also RISM 800190023 1.1.1 Allegro
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.