1. Covariant description of superstrings
2. Properties of the covariant formulation of superstring theories
3. Classical superstring mechanics
4. E. Witten, (2+1)-dimensional gravity as an exactly soluble systems, IAS Princeton preprint IASSNS-HEP-88/32.
5. E. Witten, Quantum field theory and the Jones polynomial, IAS Princeton preprint IASSNS-HEP-88/33 (expanded version of lecture at the IAMP congress, Swansea).