1. Infinite conformal symmetry in two-dimensional quantum field theory
2. Conformal invariance, supersymmetry and string theory
3. Unified String Theories;Friedan,1986
4. Unified String Theories;Shenker,1986
5. E. Martinec, String Calculus: Conformal Field Theory as a Tool in String Field Theory, Lectures given at the 1987 Spring School on Superstrings, Trieste, University of Chicago preprint EFI 87–45.