1. A. Connes, Non-commutative Geometry, Academic Press, New York, 1994.
2. J. Madore, An Introduction to Non-commutative Differential Geometry and its Applications, CUP, 1995. gr-qc/9906059
3. G. Landi, An Introduction to Non-commutative Spaces and Their Geometries, Springer, Berlin, 1997. hep-th/9701078
4. J.M. Garcia-Bondiá, J.C. Varilly, H. Figueroa, Elements of Non-commutative Geometry, Birkhauser, Basel, 2001.
5. H. Grosse, C. Klimčı́k, P. Prešnajder, Int. J. Theoret. Phys. 35 (1996) 231–244. hep-th/9505175.