@article{GDZPPN002412837, title = {The Residual Finiteness of Certain Amalgameted Free Products.}, journal = {Mathematische Zeitschrift}, volume = {135}, year = {1973}, pages = {179-182}, zbl = {0251.20034}, url = {http://dml.mathdoc.fr/item/GDZPPN002412837} }
Tretkoff, Martin. The Residual Finiteness of Certain Amalgameted Free Products.. Mathematische Zeitschrift, Tome 135 (1973) pp. 179-182. http://gdmltest.u-ga.fr/item/GDZPPN002412837/