Methodischer Leitfaden für Clavierlehrer, 1855 title page (Julius Knorr)
MGG, 2. neubearb. Ausg. (Knorr, Julius; born Sept. 22, 1807, died June 17, 1861, Leipzig; pianist and piano teacher; member of the Davidsbund [circle of musicians around Robert Schumann]; editor of the Neue Zeitschrift für Musik, April 1834 to the beginning of 1835; edited piano music for various German publishers)