'''Piano Sonata No. 4 in C minor, Op. 29 (1917)''' is a sonata composed for solo piano. It was first performed by the composer on April 17, 1918, in Petrograd.Berman, Boris. (2008). ''Prokofiev's piano sonatas: a guide for the listener and the performer.'' ISBN 978-0-300-11490-4. The work was dedicated to Prokoviev's good friend Maximilian Schmidthof, whose suicide in 1913 shocked and saddened the composer.