  Let $(G,X)$ be a Shimura variety of PEL type such that $G_{{\bf Q}_2}$ is a
split ${\bf GSO}_{2n}$ group with $n\ge 2$. We prove the existence of the
integral canonical models of ${\rm Sh}(G,X)/H_2$ in unramified mixed
characteristic $(0,2)$, where $H_2$ is a hyperspecial subgroup of $G({\bf
Q}_2)$.

Number Theory;Algebraic Geometry