28 Études de Virtuosité by Patrice Sciortino is quite possibly the most challenging etude book for the euphonium. These 28 etudes are meant to test virtuosity and to better even the 'best' player. From the author's note: "Originally conceived in C, these studies may also be performed in Bb. Each study in this collection may be performed in concert as a solo piece for euphonium (tenor tuba) or saxhorn. Some passages have been quite intentionally left without nuance or tempo marking for the performer to determine his or her own."
solo parts included: BC