1. Farrell, F.T., Hsiang, W.C.: A formula forK 1 R ?[T]. Applications of categorical algebra. Proceedings of Symposia in Pure Mathematics, Vol. XVII, AMS, 1970
2. Fox, R.H.: A quick trip through Knot theory. Topology of 3-Manifolds and related topics, Prentice-Hall, Inc., 1962
3. King, H.: Real analytic germs and their varieties at isolated singular points. Invent. Math.37, 193?199 (1976)