Voir la notice de l'article provenant de la source Math-Net.Ru
@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/} }
J.-P. Serre. Arbres, amalgames et ${SL}_2$. Matematika, Tome 18 (1974) no. 2, pp. 3-27. http://geodesic.mathdoc.fr/item/MAT_1974_18_2_a0/