@article{VMUMM_1988_6_a12,
     author = {V. V. Kozlov},
     title = {The dynamics of systems with nonintegrable constraints. {V.~The} freedom principle and a condition for ideal constraints},
     journal = {Vestnik Moskovskogo universiteta. Matematika, mehanika},
     pages = {51--54},
     publisher = {mathdoc},
     number = {6},
     year = {1988},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/VMUMM_1988_6_a12/}
}