P^2-reducing and toroidal Dehn fillings
  We study the situation where we have two exceptional Dehn fillings on a given hyperbolic 3-manifold. We consider two cases that one filling creates a projective plane, and the other creates an essential torus or a Klein bottle, and give the best possible upper bound on the distance between two fillings for each case. 
Gyo Taek Jin, Sangyop Lee, Seungsang Oh, Masakazu Teragaito