Horn trio can mean a work written for three horns or horns as well as one for horn and two other instruments. In the latter category, an important genre is the trio for horn, violin and piano. Although there are a few earlier examples, the tradition of this scoring was inaugurated in 1865 by Johannes Brahms with his Trio in E♭, opus 40. Related combinations are those of (1) oboe, horn, and piano, (2) clarinet, horn, and piano, (3) horn, bassoon, and piano and (4) flute, horn, and piano.
Amsterdam: Edition Ka We, 1970 (arr. by Edmond Leloir for violin [or flute or clarinet], horn, and piano); [Wernigerode]: Ostermeyer, 2011 (arr. by Robert Ostermeyer for violin [or flute], horn, and piano)
Frédéric Duvernoy
Trio no. 2 in F major, for oboe, horn, and piano
before 1838
Amsterdam: Edition Ka We, 1965 (arr. by Edmond Leloir for violin [or flute or clarinet], horn, and piano); [Wernigerode]: Ostermeyer, 2011 (arr. by Robert Ostermeyer for violin, horn, and piano)
Frédéric Duvernoy
Trio no. 3 for oboe, horn, and piano
before 1838
[Wernigerode]: Ostermeyer, 2011 (arr. by Robert Ostermeyer for violin [or flute], horn, and piano)