@article{MAT_1974_18_2_a0,
     author = {J.-P. Serre},
     title = {Arbres, amalgames et ${SL}_2$},
     journal = {Matematika},
     pages = {3--27},
     publisher = {mathdoc},
     volume = {18},
     number = {2},
     year = {1974},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MAT_1974_18_2_a0/}
}