@article{KUMEM_1995_3_a4,
     author = {H. S. M. Coxeter},
     title = {Angles and arcs in the hyperbolic plane},
     journal = {In memoriam N. I. Lobatschevskii},
     pages = {120--134},
     publisher = {mathdoc},
     volume = {3},
     year = {1995},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/KUMEM_1995_3_a4/}
}