@article{GDZPPN002425416,
title = {Aspherical Group Presentations.},
journal = {Mathematische Zeitschrift},
volume = {177},
year = {1981},
pages = {1-36},
zbl = {0443.20030},
url = {http://dml.mathdoc.fr/item/GDZPPN002425416}
}
Collins, Donald J.; Chiswell, Ian M. Aspherical Group Presentations.. Mathematische Zeitschrift, Tome 177 (1981) pp. 1-36. http://gdmltest.u-ga.fr/item/GDZPPN002425416/