Title: Surgery on $\widetilde {\Bbb {SL}}\times {\Bbb E}^n$-manifolds.

Abstract: We show that although closed $\widetilde{\Bbb{SL}}\times\Bbb{E}^n$-manifolds
do not admit metrics of nonpositive sectional curvature, the arguments of
Farrell and Jones can be extended to show that such manifolds are topologically
rigid, if $n\geq2$.