Mathematical Sciences: Yang-Baxter Operators, Quantum Field Theories and Invariants in Low-Dimensional Topology via HopfAlgebras and Representations of Monoidal CategoriesYetter, DavidNational Science Foundation (NSF), Directorate for Mathematical & Physical Sciences, Division of Mathematical Sciences (ID: 9296069), $3,200USD, 10/30/1991 -- 06/30/1992