@article{GDZPPN002318385, title = {Atkin-Lehner Operators.}, journal = {Mathematische Annalen}, volume = {243}, year = {1979}, pages = {121-124}, zbl = {0405.10020}, url = {http://dml.mathdoc.fr/item/GDZPPN002318385} }
Flath, Daniel. Atkin-Lehner Operators.. Mathematische Annalen, Tome 243 (1979) pp. 121-124. http://gdmltest.u-ga.fr/item/GDZPPN002318385/