@article{MZ_1974__136_172034,
     author = {Helmut Klingen},
     title = {Zur {Struktur} der {Siegelschen} {Modulgruppe.}},
     journal = {Mathematische Zeitschrift},
     pages = {169--178},
     publisher = {mathdoc},
     volume = {136},
     year = {1974},
     zbl = {0268.20034},
     url = {http://geodesic.mathdoc.fr/item/MZ_1974__136_172034/}
}