Four-dimentional Gradient Shrinking Solitons with Positive Isotropic   Curvature
  We show that a four-dimensional complete gradient shrinking Ricci soliton with positive isotropic curvature is either a quotient of S^4 or a quotient of S^3 cross R. This gives a clean classification result removing the earlier additional assumptions in [13] by Wallach and the second author. 
Xiaolong Li, Lei Ni, and Kui Wang
math.DG