Fermionic Path Integrals and Analytic Solutions for Two-Dimensional   Ising Models
  The notion of the integral over the anticommuting Grassmann variables (nonquantum fermionic fields) seems to be the most powerful tool in order to extract the exact analytic solutions for the 2D Ising models on simple and more complicated lattices, which is the subject of a discussion in this report. 
V.N. Plechko (Bogoliubov Lab Dubna)