Representations of simple lie groups II: Addendum et corrigendum

The aim of this article is to correct and expand on our previous paper with the same title (Rep. Math. Phys. 32 (1993), 351). When the centre of a compact simple Lie group is Z2 or {Z2}2, there are not necessarily irreducible representations of quaternionic type. From the periodicity of the Clifford algebra we conclude that the groups Spin(8k + e), e = ± 1,0 have only real representations. For all the other cases in the family there are quaternionic representations.