Elisabeth Hufnagel, MAPhoto: CSMCMusicologyAlumnaAddressUniversity of HamburgCentre for the Study of Manuscript Cultures (CSMC)ContactEmail: Elisabeth.Hufnagel"AT"studium.uni-hamburg.deORCID: 0000-0001-7173-7366Projects Dissertation Project Proportion Signs in the Manuscripts of the So-Called Ars subtilior: Musical Notation between Individualisation and Standardisation