Portnoff, was a violinist and teacher.He was a professor at the Stern Conservatory in Berlin from 1906 to 1915 and moved to the USA in 1922. He composed a large body of works for his student. His catalog of works include concertos, concertinos, salon style pieces and violin etudes.
Here is his Violin Concertino Op.9 in D minor which can be played in first position.
Members can download the score here
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