On a Superlinear Ambrosetti–Prodi Problem in Besov and Triebel–Lizorkin Spaces

The paper deals with superlinear elliptic boundary‐value problems in Besov and Triebel–Lizorkin spaces. The methods for inversion of differentiable maps with singularities going back to A. Ambrosetti and G. Prodi are generalized for dual rich quasi‐Banach spaces.