@article{MZ_1990__204_3_183760,
     author = {M. Marshall and L. Walter},
     title = {Signatures of {Higher} {Level} on {Rings} with {Many} {Units.}},
     journal = {Mathematische Zeitschrift},
     pages = {129--144},
     publisher = {mathdoc},
     volume = {204},
     number = {3},
     year = {1990},
     zbl = {0676.10016},
     url = {http://geodesic.mathdoc.fr/item/MZ_1990__204_3_183760/}
}