@Article{ Vit14, author = { Vittone, Davide }, title = { The regularity problem for sub-Riemannian geodesics }, journal = { Geometric measure theory and real analysis, CRM Series, Ed. Norm., Pisa. }, year = { 2014 }, volume = { 17 }, pages = { 193--226 }, URL = { http://cvgmt.sns.it/paper/2416/ }, note = { cvgmt preprint} }