@article{AL_1983_22_2_a7,
     author = {V. A. Churkin},
     title = {On the theory of groups acting on trees},
     journal = {Algebra i logika},
     pages = {218--225},
     publisher = {mathdoc},
     volume = {22},
     number = {2},
     year = {1983},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_1983_22_2_a7/}
}