Groups of units of integral group rings commensurable with direct   products of free-by-free groups
  We classify the finite groups $G$ such that the group of units of the integral group ring ${\mathbb Z} G$ has a subgroup of finite index which is a direct product of free-by-free groups. 
Eric Jespers (1), Antonio Pita (2), Angel del Rio (2), Manuel Ruiz   (3), Pavel Zalesski (4) ((1) Vrije Universiteit Brussel...