• Apel, Willi. 1953. The notation of polyphonic music, 900-1600. Cambridge, Mass.: Mediaeval Academy of America. Subject: Musical notation.

 

  • Berger, Anna Maria Busse. 1993. Mensuration and proportion signs : origins and evolution. Oxford, England: Clarendon Press; New York: Oxford University Press .

 

  • Parrish, Carl. 1957. The notation of medieval music. New York : Norton. Subject: Musical notation.

 

  • Parrish, Carl. 1946. The Notation of Medieval Music. New York: Carl Fischer, Inc.

 

  • Patch, Harry. 1949. Genesis of a Music. Madison: University of Wisconsin Press.