
 AXIOMS 
  Any one of these axioms together with the axioms of Neutral geometry (incidence axioms I1, I2, I3; betweenness axioms B1, B2, B3, B4; congruence axioms C1, C2, C3, C4, C5, C6; and Dedekind's continuity axiom) give a complete system of axioms for the Euclidean geometry. 
  Perspectivities preserve separation; i.e., if (A, BC, D), with l the line through A, B, C, and D, and P, Q, R, and S are the corresponding points on line m under a perspectivity, then (P, QR, S). 
  * in elliptic geometry the betweenness axioms are replaced with separation axioms. 
 www.southernct.edu /~pinciuv/m360axio.html (960 words) 
