Pischna, J. 1., Wolff, B. 1., & Baker, T. 1. (1931). Technical studies: Sixty progressive exercises, containing studies on trills, scales, chords, passages and arpeggios for the pianoforte (Newly revised and augmented edición with additional preliminary exercises by Bernard Wolff.). New York: G. Schirmer.

Pischna, Johann 1826-1896, Bernhard 1835-1906 Wolff, and Theodore 1851-1934 Baker. Technical Studies: Sixty Progressive Exercises, Containing Studies On Trills, Scales, Chords, Passages and Arpeggios for the Pianoforte. Newly revised and augmented edición with additional preliminary exercises by Bernard Wolff. New York: G. Schirmer, 1931.

Pischna, Johann 1826-1896, Bernhard 1835-1906 Wolff, and Theodore 1851-1934 Baker. Technical Studies: Sixty Progressive Exercises, Containing Studies On Trills, Scales, Chords, Passages and Arpeggios for the Pianoforte. Newly revised and augmented edición with additional preliminary exercises by Bernard Wolff. New York: G. Schirmer, 1931.