TY  - JOUR
AU  - P. Haukkanen
AU  - J. K. Merikoski
AU  - T. Tossavainen 
TI  - Axiomatizing Perpendicularity and Parallelism
JO  - Journal for geometry and graphics
PY  - 2011
SP  - 129
EP  - 139
VL  - 15
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/JGG_2011_15_2_JGG_2011_15_2_a1/
ID  - JGG_2011_15_2_JGG_2011_15_2_a1
ER  -