Egon Wellesz, Dom Anselm Hughes and Gerald Abrahan - The New Oxford History of Music, vol 1, 2 and 3 ( Oxford University Press ) 1957/1954/1960

https://ignca.gov.in

https://hugoribeiro.com.br

https://vdoc.pub/

https://ignca.gov.in/Asi_data/16178.pdf

https://hugoribeiro.com.br/biblioteca-digital/Hughes-Early_Medieval_Music_to_1300.pdf

https://vdoc.pub/download-file/ars-nova-and-the-renaissance-1300-1540-r7vi7ul0fs80?hash=c2248c0038b0940294ed4e0698592b30