On Verlinde sheaves and strange duality over elliptic Noether-Lefschetz   divisors
  We extend results on generic strange duality for K3 surfaces by showing that the proposed isomorphism holds over an entire Noether-Lefschetz divisor in the moduli space of quasipolarized K3s. We interpret the statement globally as an isomorphism of sheaves over this divisor, and also describe the global construction over the space of polarized K3s. 
Alina Marian, Dragos Oprea
math.AG