Addendum to "Classification of irreducible holonomies of torsion-free affine connection"

Abstract

The real form Spin(6,H) in End(R^{32}) of Spin(12,C) in End(C^{32}) is absolutely irreducible and thus satisfies the algebraic identities (40) and (41). Therefore, it also occurs as an exotic holonomy and the associated supermanifold M_g admits a SUSY-invariant polynomial. This real form has been erroneously omitted in our paper. Also, the two real four-dimensional exotic holonomies, whose occurrences were un known at the time of writing, have been shown to exist very recently by R. Bryant.