It is not known when Mozart completed his Concerto for Two Pianos and Orchestra in E-flat major, K. 365/316a, but research by Alan Tyson shows that cadenzas for the first and third movements are written in his and his father's handwriting on a... Wikipedia
Composed: 1779
Composer: Wolfgang Amadeus Mozart
Key: E-flat major
Movements: Three (Allegro, Andante, Rondo: Allegro)
Scoring: 2 pianos; orchestra