APA (7th ed.) Citation

Apel, W. (1949). The notation of polyphonic, 900-1600. 4th ed., rev. and with commentary. Mediaeval academy of America.

Chicago Style (17th ed.) Citation

Apel, Willi. The Notation of Polyphonic, 900-1600. 4th Ed., Rev. and with Commentary. Cambridge, Mass: Mediaeval academy of America, 1949.

MLA (9th ed.) Citation

Apel, Willi. The Notation of Polyphonic, 900-1600. 4th Ed., Rev. and with Commentary. Mediaeval academy of America, 1949.