TY  - JOUR
AU  - Christoph Hering
AU  - Michael Walker
TI  - Perspectivities in Irreducible Collineation Groups of Projective Planes. I.
JO  - Mathematische Zeitschrift
PY  - 1977
SP  - 95
EP  - 102
VL  - 155
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MZ_1977__155_172547/
ID  - MZ_1977__155_172547
ER  -