Britton, D. T.Hempel, A.Triftshäuser, W.2004-12-032004-12-0320012001http://hdl.handle.net/2003/169910.17877/DE290R-11475enThe American Physical SocietyPhysical Review Letters530Hopping Transport of Positrons in Hydrogenated Amorphous Silicon10.1103/PhysRevLett.87.217401article (journal)