TY  - JOUR
AU  - Lowenthal, Franklin
TI  - On Subsemigroups of the Projective Group on the Line
JO  - Canadian journal of mathematics
PY  - 1968
SP  - 1001
EP  - 1011
VL  - 20
IS  - 1
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CJM-1968-097-7/
DO  - 10.4153/CJM-1968-097-7
ID  - 10_4153_CJM_1968_097_7
ER  -