1. Embeddings of the line in the plane;Abhyankar;J. Reine Angew. Math.,1975
2. An Introduction to Gröbner Bases;Adams,1994
3. Free Rings and their Relations;Cohn,1985
4. A commutator test for two elements to generate the free algebra of rank two;Dicks;Bull. London Math. Soc.,1982
5. Three-dimensional Link Theory and Invariants of Plane Curve Singularities;Eisenbud,1985