@article{TRSPY_1995_209_a7,
     author = {S. K. Lando},
     title = {Deformations of differentials forms},
     journal = {Informatics and Automation},
     pages = {167--199},
     publisher = {mathdoc},
     volume = {209},
     year = {1995},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TRSPY_1995_209_a7/}
}