1. Global theory of elliptic operators;Atiyah,1970
2. On topological obstructions to integrability;Boft;ICM Nice,1970
3. Non commutative differential geometry;Connes;Publ. I.H.E.S.,1985
4. The action functional in non-commutative geometry;Connes;Comm. Math. Phys.,1988
5. Non commutative geometry;Connes,1994