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{\bf Endotrivial irreducible lattices}\\
\emph{Geoffrey R. Robinson,\\ Institute of Mathematics, University of Aberdeen,\\September 2010}
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\begin{abstract}
We consider the structure of a finite group which has a faithful irreducible endotrivial
$RG$-module for a suitable complete discrete valuation ring $R$ with $R/J(R)$ of characteristic $p.$
\end{abstract}