@article{1077374666,
author = {Turrittin, H. L.},
title = {Reducing the rank of ordinary differential equations},
journal = {Duke Math. J.},
volume = {30},
number = {1},
year = {1963},
pages = { 271-274},
language = {en},
url = {http://dml.mathdoc.fr/item/1077374666}
}
Turrittin, H. L. Reducing the rank of ordinary differential equations. Duke Math. J., Tome 30 (1963) no. 1, pp. 271-274. http://gdmltest.u-ga.fr/item/1077374666/