Mozart, Concerto No. 4 in D Major K218 for Violin (Zen-On)

Mozart's "Romantic Sonatas" for violin and piano have uncertain authorship. The original autographs are missing, and the publisher, Breitkopf & Härtel, doubted their authenticity. Konstanze, Mozart's wife, offered the sonatas to the publisher in 1799, but they were disappointed and requested the original manuscript. However, it could not be found, adding to Konstanze's doubts.