@article{MZ_1991__207_2_174278,
     author = {Pilar Bayer and Gerhard Frey},
     title = {Galois representations of octahedral type and 2-coverings of elliptic curves.},
     journal = {Mathematische Zeitschrift},
     pages = {395--408},
     publisher = {mathdoc},
     volume = {207},
     number = {2},
     year = {1991},
     zbl = {0712.11035},
     url = {http://geodesic.mathdoc.fr/item/MZ_1991__207_2_174278/}
}