@article{CHEB_2014_15_1_a3,
     author = {V. N. Bezverkhniy and I. V. Dobrynina},
     title = {On free subgroup in {Artin} group with tree-structure},
     journal = {\v{C}eby\v{s}evskij sbornik},
     pages = {32--42},
     publisher = {mathdoc},
     volume = {15},
     number = {1},
     year = {2014},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/CHEB_2014_15_1_a3/}
}