@article{MZ_1973__132_171925,
     author = {Gerhard Rosenberger},
     title = {Eine {Bemerkung} zu den {Triangel-Gruppen.}},
     journal = {Mathematische Zeitschrift},
     pages = {239--244},
     publisher = {mathdoc},
     volume = {132},
     year = {1973},
     zbl = {0251.20035},
     url = {http://geodesic.mathdoc.fr/item/MZ_1973__132_171925/}
}