Emmanuel Briand Equations, inequations and inequalities characterizing the configurations of two real projective conics. 21-52 2007 18 Appl. Algebra Eng. Commun. Comput. 1-2 http://dx.doi.org/10.1007/s00200-006-0023-8 db/journals/aaecc/aaecc18.html#Briand07