@article{GDZPPN002443066,
title = {Thetanullwerte and stable modular forms for Hecke groups.},
journal = {Mathematische Zeitschrift},
volume = {217},
year = {1994},
pages = {529-540},
zbl = {0814.11029},
url = {http://dml.mathdoc.fr/item/GDZPPN002443066}
}
Manni, Riccardo Salvati. Thetanullwerte and stable modular forms for Hecke groups.. Mathematische Zeitschrift, Tome 217 (1994) pp. 529-540. http://gdmltest.u-ga.fr/item/GDZPPN002443066/