J.S. Bach (c. 1710): Concerto in D Major After Vivaldi, BWV 972
After Antonio Vivaldi, Concerto for Five Violins And Continuo, RV 230
II. Larghetto

This is a remarkable musical curiosity: a bona fide co-composition by the two Baroque giants, Johann Sebastian Bach and Antonio Vivaldi. Relatively early in his career, Bach came across Vivaldi's earliest published concertos and was sufficiently impressed that he transcribed them for solo harpsichord (with various alterations and additions of his own). When these transcriptions were redicovered and published in the 19th century (by which time Bach was idolised and Vivaldi almost entirely forgotten), they kickstarted the great Vivaldi revival of the 20th century. There is more background on these transcriptions at Wikipedia.
My recording for mandolin quartet of the larghetto from the first of the transcribed harpsichord concertos is based on a string quartet arrangements by Mike Magatagan at:
https://musescore.com/mike_magatagan/scores/4455701
This transfers to mandolins really nicely, possibly because of the similarity in the tonality to the harpsichord. Comparing Bach's version with Vivaldi's, the melody line is almost verbatim Vivaldi, with some modifications in the harmonisation.
1890s Umberto Ceccherini mandolin
Mid-Missouri M-0W mandolin
Mid-Missouri M-111 octave mandolin
Suzuki MC-815 mandocello

Martin