Ga. Elliott et al., THE ATIYAH-SINGER INDEX THEOREM AS PASSAGE TO THE CLASSICAL LIMIT IN QUANTUM-MECHANICS, Communications in Mathematical Physics, 182(3), 1996, pp. 505-533
A new approach to the Atiyah-Singer index theorem is described, using
the technique of continuous fields of C-algebras. The proof is given
in the case of elliptic pseudodifferential operators on IR(n).