Bach in July I wrote about these pieces. They are originally written for clarinet, and are the last chamber pieces Brahms wrote in his life. Brahms himself wrote this version for violin. Here it is performed by Jenny Abel, a German violinist born in 1942.
I didn’t know Jenny Abel (and there seem to be a lot of other people with that name). I am impressed with the performance on this record though. Roberto Szidon was a Brazilian pianist of around the same age. On his wiki page it is mentioned that he worked a lot with Jenny Abel, but I haven’t found any other recordings of the two.