@article{ASUO_2016_XXIV_2_a14,
     author = {Bilal Demir and Ozden Koruoglu and Recep Sahin},
     title = {On {Normal} {Subgroups} of {Generalized
}                            {Hecke} {Groups}},
     journal = {Analele Universit\u{a}\c{t}ii "Ovidius" Constan\c{t}a Seria Matematic\u{a}},
     publisher = {mathdoc},
     volume = {XXIV},
     number = {2},
     year = {2016},
     url = {http://geodesic.mathdoc.fr/item/ASUO_2016_XXIV_2_a14/}
}