@article{GDZPPN002418754,
title = {Infinitely Generated Subgroups of Finitely Presented Groups.I.},
journal = {Mathematische Zeitschrift},
volume = {154},
year = {1977},
pages = {117-134},
zbl = {0332.20009},
url = {http://dml.mathdoc.fr/item/GDZPPN002418754}
}
Baumslag, Gilbert; Cannonito, Frank B. Infinitely Generated Subgroups of Finitely Presented Groups.I.. Mathematische Zeitschrift, Tome 154 (1977) pp. 117-134. http://gdmltest.u-ga.fr/item/GDZPPN002418754/