Coxeter - Figure 1.6 A (left)
A, B, and C are the instances of the variable point X while a ,b , and c are the instances of the variable line x. We can say ABC is perspective with respect to the point O to A'B'C'.
Carbon Dioxide and Temperature
Cube Cross Section
Homothety in Three Tangent Circles
coplanar and point and lines
9.1.3 Pre #1103407 option D
[+Quantum Continuum]: En - [graphical method]