1. Topological Quantum Field Theory;Witten;Commun. Math. Phys.,1988
2. Introduction to Cohomological Field Theories;Witten,1991
3. For a review, see S. Cordes, G. Moore, and S. Ramgoolam, “Lectures on 2D Yang Mills theory, Equivariant Cohomology, and Topological String Theory,” Lectures presented at the 1994 Les Houches Summer School “Fluctuating Geometries in Statistical Mechanics and Field Theory.” and at the Trieste 1994 Spring school on superstrings hep-th/9411210, orsee http://xxx.lanl.gov/lh94.
4. Conformal Invariance, Supersymmetry and String Theory;Friedan;Nucl. Phys.,1986
5. A. Losev, G. Moore, N. Nekrasov, S. Shatashvili, in preparation.