Max Reger - Bange Frage

Max Reger (Mar. 19, 1873 - May 11, 1916) was a German composer, pianist, organist, conductor, and teacher.
Sheet music: imslp.org/wiki/Aus_der_Jugend...)

[@Herr_Flick_of_ze_Gestapo]

surely this piece was written for the harmonium.