@article{GDZPPN002441365,
title = {A cyclically pinched product of free groups which is not residually free.},
journal = {Mathematische Zeitschrift},
volume = {212},
year = {1993},
pages = {533-534},
zbl = {0795.20014},
url = {http://dml.mathdoc.fr/item/GDZPPN002441365}
}
Levin, F.; Rosenberger, G.; Baumslag, B. A cyclically pinched product of free groups which is not residually free.. Mathematische Zeitschrift, Tome 212 (1993) pp. 533-534. http://gdmltest.u-ga.fr/item/GDZPPN002441365/