Henri Dulac
![Henri Dulac](https://upload.wikimedia.org/wikipedia/commons/3/39/Henri_Dulac.jpg)
1
Published: 1936
Superior document: Leonhardi Euleri opera omnia Series 1, Opera mathematica, Vol. 22
2
Published: 1938
Superior document: Leonhardi Euleri opera omnia Series 1, Opera mathematica, Vol. 23