Grand Trio Concertante Op31

Grand Trio Concertant, Opus 31 composed by Johann Wilhelm Gabrielsky (1791-1846)
Edited by Albert J. Andraud for 3 Flutes
Includes score and parts

A German flutist of the early 19th century, this trio does have the melodic line being shared between the parts.  

Contents: 
Movements:
Allegro con giusto
Theme with four variations
Rondo

(The fourth variation does have a cadenza in the first part, which leads into the Rondo section.)