4 General introduction
Classical symbolic calculus
of pseudo-differential
operators
Elliptic perturbation
situations
Wave front set
Propagation of
singularities
Nash-Moser theorem
Fixed-point
situations
In this spirit, we were recently very happy to learn of the work of
L. Hormander [H9], explaining the links between pseudo-differential and
paradifferential operators, fixed-point methods and the Nash-Moser theo-
rem.
Finally, we are grateful to G. Ben Arous and J.B. Bost for their kind
and valuable suggestions.
