@article{GDZPPN002422646,
title = {Order Reduced Reidemeister-Schreier Subgroup Presentations and Applications.},
journal = {Mathematische Zeitschrift},
volume = {166},
year = {1979},
pages = {53-70},
zbl = {0388.20027},
url = {http://dml.mathdoc.fr/item/GDZPPN002422646}
}
Zieschang, Heiner; Gramberg, Edelgard. Order Reduced Reidemeister-Schreier Subgroup Presentations and Applications.. Mathematische Zeitschrift, Tome 166 (1979) pp. 53-70. http://gdmltest.u-ga.fr/item/GDZPPN002422646/