TY  - JOUR
AU  - Lyndon, R. C.
AU  - Ullman, J. L.
TI  - Groups Generated by two Parabolic Linear Fractional Transformations
JO  - Canadian journal of mathematics
PY  - 1969
SP  - 1388
EP  - 1403
VL  - 21
IS  - 1
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CJM-1969-153-1/
DO  - 10.4153/CJM-1969-153-1
ID  - 10_4153_CJM_1969_153_1
ER  -