Mozart's Twelfth Mass, K. Anh. 232 Mozart's Twelfth Mass, K. Anh. 232 Mozart's Twelfth Mass, once a top seller among the liturgical compositions published by Vincent Novello in the 19th century, is a work no longer attributed to Wolfgang Amadeus Mozart. Köchel rejected the attribution to Mozart in the Anhang (appendix) of the first edition of his catalogue of Mozart's works, there listed as K. Anh. 232, and in later editions as K. Anh. C1.04. The mass was published in 1819 as No. 12 in Novello's series of masses by Mozart, which is the origin of its name. Simrock was the first to publish the mass
Köchel catalogue and Georges de St. Foix) reassigned a number of works from the original K appendices into the main catalogue by interpolating new numbers into the main sequence with a lower-case letter suffix. In K some of these were reassessed in the light of scholarship since 1937 and returned to the re-worked appendices: For example, the Divertimento for Wind Octet in E♭ was numbered Anh. 226 in K; Einstein placed it in the K main catalogue as K. 196e, between K. 196 and K. 197; K reassigned it again to the 'doubtful' appendix C as Anh. C 17.01. Some works in