1. Introduction to Commutative Algebra;Atiyah,1969
2. Valuations and finitely presented metabelian groups;Bieri;Proc. London Math. Soc.,1980
3. A geometric invariant for modules over an Abelian group;Bieri;J. Reine Angew. Math.,1981
4. An Introduction to the Geometry of Numbers;Cassels,1959
5. Analytic pro-p groups;Dixon,1991