A new approach for calculating the Nambu-Gorkov propagator in color   superconductivity theory
  In this article, we propose a new approach to calculate the Nambu-Gorkov propagator intuitively with some linear algebra techniques in presence of the scalar diquark condensates. With the help of energy projective operators, we can obtain relatively simple expressions for the quark propagators, which greatly facilitate the calculations in solving the Schwinger-Dyson equation to obtain the gap parameters. 
Z. G. Wang, S. L. Wan, W. M. Yang