01 The Classical Music Score Digitization Project
https://cmsdp.org/start

02 Josquin Research Project, Standford University
http://jrp.stanford.edu

03 Kern Scores
http://kern.ccarh.org/

04 Tobi's Notenarchiv
http://www.tobis-notenarchiv.de/noten/index.htm

05 Kantionalsätze von Sethus Calvisius in der Edition von Dr. Franz Kaern-Biederstedt

07 Music21 Corpus, MIT
https://web.mit.edu/music21/doc/about/referenceCorpus.html