Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MAN_1980__252_163456, author = {Jing Yu}, title = {A {Cuspidal} {Class} {Number} {Formula} for the {Modular} {Curves} {X1(N).}}, journal = {Mathematische Annalen}, pages = {197--216}, publisher = {mathdoc}, volume = {252}, year = {1980}, zbl = {0426.12003}, url = {http://geodesic.mathdoc.fr/item/MAN_1980__252_163456/} }
Jing Yu. A Cuspidal Class Number Formula for the Modular Curves X1(N).. Mathematische Annalen, Tome 252 (1980), pp. 197-216. http://geodesic.mathdoc.fr/item/MAN_1980__252_163456/