@article{GDZPPN002486644, title = {A Note on the Amenable Subgroups of PSL (2, R).}, journal = {Monatshefte f\"ur Mathematik}, volume = {108}, year = {1989}, pages = {241-244}, zbl = {0679.43008}, url = {http://dml.mathdoc.fr/item/GDZPPN002486644} }
Nebbia, Claudio. A Note on the Amenable Subgroups of PSL (2, R).. Monatshefte für Mathematik, Tome 108 (1989) pp. 241-244. http://gdmltest.u-ga.fr/item/GDZPPN002486644/