Imrich, W., and Razen, R.. "On the number of subgroups of given index in the modular group.." Monatshefte für Mathematik 87 (1979): 273-280. <http://eudml.org/doc/177918>.
@article{Imrich1979, author = {Imrich, W., Razen, R.}, journal = {Monatshefte für Mathematik}, keywords = {Number of Subgroups of Given Index in the Modular Group}, pages = {273-280}, title = {On the number of subgroups of given index in the modular group.}, url = {http://eudml.org/doc/177918}, volume = {87}, year = {1979}, }
TY - JOUR AU - Imrich, W. AU - Razen, R. TI - On the number of subgroups of given index in the modular group. JO - Monatshefte für Mathematik PY - 1979 VL - 87 SP - 273 EP - 280 KW - Number of Subgroups of Given Index in the Modular Group UR - http://eudml.org/doc/177918 ER -
