Non-arithmetic lattices and the Klein quartic
  We give an algebro-geometric construction of some of the non-arithmetic ball quotients constructed by the author, Parker and Paupert. The new construction reveals a relationship between the corresponding orbifold fundamental groups and the automorphism group of the Klein quartic, and also with groups constructed by Barthel-Hirzebruch-H\"ofer and Couwenberg-Heckman-Looijenga. 
Martin Deraux
math.AG math.DG math.GT