Smooth approximation of bi-Lipschitz orientation-preserving homeomorphisms
Sara Daneri, Aldo M. Pratelli · Annales de l Institut Henri Poincaré C Analyse Non Linéaire · 2013
We show that a planar bi-Lipschitz orientation-preserving homeomorphism can be approximated in the W^{1,p} norm, together with its inverse, with an orientation-preserving homeomorphism which is piecewise affine or smooth.