@article{LJM_2006_23_a6,
     author = {M. A. Malakhaltsev},
     title = {Differential complex associated to closed differential forms of nonconstant rank},
     journal = {Lobachevskii journal of mathematics},
     pages = {183--192},
     publisher = {mathdoc},
     volume = {23},
     year = {2006},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/LJM_2006_23_a6/}
}