Most of César Franck's works seem to have been published during his lifetime, although only 21 works received a publisher's opus number. The mature published works were catalogued by Wilhelm Mohr in his Franck Werke Verzeichnis (FWV). He divided Franck's compositions into two main groups: instrumental works, M.1-48, and vocal works, M.49-91, arranging them by genre, and by composition date order within each genre. The CFF catalogue (see § External links) compiled by Joël-Marie Fauquet (published in 1999) details almost every known work by Franck, including many not listed by Mohr. In addition, many dates are listed in Fauquet's catalogue that are incorrect in Mohr's, or missing altogether. In 2022, a critical 8-volume edition of the complete organ and harmonium works by Franck was published by Lyrebird Music, which follows the CFF catalogue and includes previously unpublished compositions.