Bach's closing chorale of BWV 8, copied by Carl Friedrich Barth, chorister at the Thomasschule
Johann Sebastian Bach
<a rel="nofollow" class="external text" href="https://www.bach-digital.de/receive/BachDigitalSource_source_00001952?lang=en">Bach digital archive</a>, a cropped version of an image originally uploaded by <a href="//commons.wikimedia.org/wiki/User:Mathsci" title="User:Mathsci">User:Mathsci</a>