Automorphisms of Twisted Chevalley Groups of type ${}^2 D_\ell \ (\ell \geq 4)$ over Local Rings

Abstract

This paper is part of a series devoted to the classification of isomorphisms and automorphisms of twisted Chevalley groups over commutative rings. In this work, we prove that every automorphism of a twisted Chevalley group of type ${}^2 D_\ell$ ($\ell \geqslant 4$) over a local ring containing $1/2$ is standard.