%0 Journal Article %A KIRSCHMER, MARKUS %A LEEDHAM-GREEN, CHARLES %T COMPUTING WITH SUBGROUPS OF THE MODULAR GROUP %J Glasgow mathematical journal %D 2015 %P 173-180 %V 57 %N 1 %U http://geodesic.mathdoc.fr/articles/10.1017/S0017089514000202/ %R 10.1017/S0017089514000202 %F 10_1017_S0017089514000202