TY  - JOUR
AU  - R. Rankin
TI  - Subgroups of the modular group defined by a single linear congruence
JO  - Acta Arithmetica
PY  - 1973
SP  - 313
EP  - 323
VL  - 24
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.4064/aa-24-3-313-323/
DO  - 10.4064/aa-24-3-313-323
LA  - en
ID  - 10_4064_aa_24_3_313_323
ER  -