@article{MZ_1975__142_172198,
     author = {Linda Keen},
     title = {A {Modular} {Group} and {Riemann} {Surfaces} of {Genus} 2.},
     journal = {Mathematische Zeitschrift},
     pages = {205--220},
     publisher = {mathdoc},
     volume = {142},
     year = {1975},
     zbl = {0286.32016},
     url = {http://geodesic.mathdoc.fr/item/MZ_1975__142_172198/}
}