@article{10_21136_MB_2003_134178,
     author = {Tekcan, Ahmet and Bizim, Osman},
     title = {The connection between quadratic forms and the extended modular group},
     journal = {Mathematica Bohemica},
     pages = {225--236},
     year = {2003},
     volume = {128},
     number = {3},
     doi = {10.21136/MB.2003.134178},
     mrnumber = {2012601},
     zbl = {1093.11024},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/MB.2003.134178/}
}