Finite-dimensional pointed Hopf algebras over finite simple groups of   Lie type II. Unipotent classes in symplectic groups
  We show that Nichols algebras of most simple Yetter-Drinfeld modules over the projective symplectic linear group over a finite field, corresponding to unipotent orbits, have infinite dimension. We give a criterium to deal with unipotent classes of general finite simple groups of Lie type and apply it to regular classes 
Nicol\'as Andruskiewitsch, Giovanna Carnovale and Gast\'on Andr\'es   Garc\'ia
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