@article{1077491907,
author = {Rodabaugh, Louis D.},
title = {The partial differential equation
$\frac{\partial z}{\partial x}+f(x,y)\frac{\partial z}{\partial y}=0$},
journal = {Duke Math. J.},
volume = {6},
number = {1},
year = {1940},
pages = { 362-374},
language = {en},
url = {http://dml.mathdoc.fr/item/1077491907}
}
Rodabaugh, Louis D. The partial differential equation
$\frac{\partial z}{\partial x}+f(x,y)\frac{\partial z}{\partial y}=0$. Duke Math. J., Tome 6 (1940) no. 1, pp. 362-374. http://gdmltest.u-ga.fr/item/1077491907/