Computing the intrinsic camera parameters using Pascal
 The authors of this paper adopted the characteristics of the 
image of the absolute conic
 in terms of Pascal's theorem to propose a new camera calibration method. 
Employing this theorem in the geometric algebra
 framework enables the authors
 to compute a projective invariant using the  conics of only
images  which expressed using brackets helps us to set enough equations to solve
calibration problem.