The maximal normal $p$-subgroup of the automorphism group of an abelian
$p$-group
Proc. Amer. Math. Soc. 126 (1998), 2525-2533.

Jutta Hausen 
Department of Mathematics, University of Houston, Houston, Texas 77204-3476 
and 
Phillip Schultz
Department of Mathematics, University of Western Australia, Nedlands 6009, 
Australia 

Abstract. Let $p$ be a prime number and let $G$ be an abelian $p$-group. 
Let $\Delta$ be the maximal normal $p$-subgroup of ${\rm Aut}(G)$ and let 
${\bf t}$ be the torsion radical of $\mathcal E(G)$. Then $\Delta =
(1+{\bf t})\zeta$. The result is new for $p=2$ and $3$, and the proof is new 
and valid for all primes $p$.