Carlson, Jon F.Thévenaz, Jacques2008-12-162008-12-162008-12-16200010.1023/A:1009988424910https://infoscience.epfl.ch/handle/20.500.14299/32738We prove that the group T(G) of endo-trivial modules for a non-cyclic finite p-group G is detected on restriction to the family of subgroups which are either elementary abelian of rank 2 or (almost) extraspecial. This result is closely related to the problem of finding the torsion subgroup of T(G). We give the complete structure of T(G) when G is dihedral, semi-dihedral, or quaternion.endo-permutation modulesindecomposable endo-trivial modulesDade groupsHeller translatesfinite $p$-groupstext::journal::journal article::research article