Home› Librettists› Hector Crémieux and Ernest Blum Librettist · Catalogued Works Hector Crémieux and Ernest Blum 2 opera libretti catalogued, listed by date of premiere. Complete Catalogue of Libretti by Hector Crémieux and Ernest Blum 1873 La jolie parfumeuse by Jacques Offenbach, 1873 Jacques Offenbach German 1874 Bagatelle by Jacques Offenbach, 1874 Jacques Offenbach German