'''Symphony No. 90''' in C major, Hoboken 1/90, was written by Joseph Haydn in 1788 as part of a three-symphony commission by Comte d'Ogny for the Concerts de la Loge Olympique.Brown, A. Peter, ''The Symphonic Repertoire'' (Volume 2). Indiana University Press (ISBN 0-253-33487-X), pp. 232-233 (2002). It is occasionally referred to as ''The Letter R'' -- referring to an older method of cataloguing Haydn's symphonic output.