@article{MAT_1968_12_5_a4,
     author = {Ya. Ihara},
     title = {Discrete subgroups of $\mathrm{PL}(2,k_\mathfrak p)$},
     journal = {Matematika},
     pages = {131--138},
     publisher = {mathdoc},
     volume = {12},
     number = {5},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MAT_1968_12_5_a4/}
}