@article{DAN_1997_354_1_a4,
     author = {L. G. Mikhailov},
     title = {On the singular theory of total differentials},
     journal = {Doklady Akademii Nauk},
     pages = {21--24},
     publisher = {mathdoc},
     volume = {354},
     number = {1},
     year = {1997},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1997_354_1_a4/}
}