Luis Antonio González and Antonio Ezquerro, both principal investigators of the project’s research entitled What is not written in written music, coordinate the First International Conference on Hispanic Musical Heritage, held in Saragossa on 8 to 10 June, with 28 lectures and sessions at the ‘Institución Fernando el Católico’  (Diputación de Zaragoza) and the Music Archive of the Cathedrals of Saragossa (E: Zac).