A Sylow theorem for the integral group ring of PSL(2,q)
  For G = PSL(2,p^f) denote by ZG the integral group ring, by V(ZG) the group of normalized units of ZG and let r be a prime different from p. Using the so called HeLP-method we prove, that units of r-power order in V(ZG) are rationally conjugate to elements of G. As a consequence we prove, that subgroups of prime power order in V(ZG) are rationally conjugate to subgroups of G, provided p = 2 or f =1. 
Leo Margolis
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