@article{05141817,
title = {Differential complex associated to closed differential forms of nonconstant rank.},
journal = {Lobachevskii Journal of Mathematics},
volume = {21},
year = {2006},
pages = {183-192},
zbl = {1118.58009},
language = {en},
url = {http://dml.mathdoc.fr/item/05141817}
}
Malakhaltsev, Mikhail A. Differential complex associated to closed differential forms of nonconstant rank.. Lobachevskii Journal of Mathematics, Tome 21 (2006) pp. 183-192. http://gdmltest.u-ga.fr/item/05141817/