TRA N SLA TIO N PLA N ES ADM IT T IN G BAER GROU PS

D efinition 21.1 Let D be a vector space net. Let 7r0 be a translation pointBaer subplane with kernel K 0.

A collineation group of D fixing ir0 pointwise and which may be identified with

is called a \full K 0 -point-Baer elation group9. A collineation group of D fixing 7r0 pointwise which may be identified

with

for all 7 in

for all 7 in

is called a ‘full K 0 -point-Baer homology group’.