  For a Coxeter group $W$ we have an associating bi-linear form $B$ on a real
vector space. We assume that $B$ has the signature $(n-1,1)$. In this case we
have the Cannon-Thurston map for $W$, that is, a $W$-equivariant continuous
surjection from the Gromov boundary of $W$ to the limit set of $W$. We focus on
the case where Coxeter groups contain affine special subgroups.
