Willi Apel
![Apel Notation](https://upload.wikimedia.org/wikipedia/commons/e/ec/Apel_Notation.jpg)
1
Published: 1949
Superior document: Publication / Mediaeval Academy of America 38
2
3
Published: 1983
Superior document: Beihefte zum Archiv für Musikwissenschaft Band 21
4
5
6
Published: 1950
Superior document: Historical anthology of music 2
7
Other Authors:
“...Apel, Willi 1893-1988...”