A Sard type theorem for Borel mappings
Volume 67 / 1994
Colloquium Mathematicum 67 (1994), 217-221
DOI: 10.4064/cm-67-2-217-221
Abstract
We find a condition for a Borel mapping $f:ℝ^m → ℝ^n$ which implies that the Hausdorff dimension of $f^{-1}(y)$ is less than or equal to m-n for almost all $y ∈ ℝ^n$.
