@article{1077465337,
author = {Herbst, Robert Taylor},
title = {Reduction of differential systems to first order},
journal = {Duke Math. J.},
volume = {20},
number = {1},
year = {1953},
pages = { 481-487},
language = {en},
url = {http://dml.mathdoc.fr/item/1077465337}
}
Herbst, Robert Taylor. Reduction of differential systems to first order. Duke Math. J., Tome 20 (1953) no. 1, pp. 481-487. http://gdmltest.u-ga.fr/item/1077465337/