A topological resolution theorem Selman Akbulut, Laurence Taylor (1981) Publications Mathématiques de l'IHÉS
An invariant of tangle cobordisms via subquotients of arc rings Yanfeng Chen, Mikhail Khovanov (2014) Fundamenta Mathematicae We construct an explicit categorification of the action of tangles on tensor powers of the fundamental representation of quantum sl(2).