@article{MZM_2000_68_5_a13,
     author = {S. G. Ivanov},
     title = {$Q${-Transformations} and $Q${-Equivalence}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {783--785},
     publisher = {mathdoc},
     volume = {68},
     number = {5},
     year = {2000},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2000_68_5_a13/}
}