@article{MOMA_1977__83_177797,
     author = {G. Rosenberger and F. Tessun},
     title = {Eine {Bemerkung} zu den {Nielsen-Transformationen.}},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {43--52},
     publisher = {mathdoc},
     volume = {83},
     year = {1977},
     zbl = {0348.20032},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1977__83_177797/}
}