Busch - who left Germany for Switzerland when the Nazis came to power due to his utter disgust with the regime - is mostly known as a performer and with the Busch Quartett as a group leader. However, he was a prolific composer. I swiped the following list in the aim of spreading the "good news," as it were. There is a two-volume biography of the man published in 2010 by Toccata Press.
There are some decent radio recordings of a few of his works that aren't out on vinyl or CD on YouTube.
Another great artist who lived and was recorded before hi-fi - damn it all.
https://s22.postimg.org/z236q0sjl/A.Busch_Complete_Works.jpg
Toccata and CPO have recent releases of some of his pieces:
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[asin]B00YCAU5WM[/asin]
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http://www.musicweb-international.com/classrev/2016/Jan/Busch_trios_7775282.htm
the string sextet, paired with a Braunfels quintet:
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