@article{JEMS_2010_12_2_a4,
     author = {Joram Lindenstrauss and David Preiss and Jaroslav Ti\v{s}er},
     title = {Fr\'echet differentiability of {Lipschitz} functions via a variational principle},
     journal = {Journal of the European Mathematical Society},
     pages = {385--412},
     year = {2010},
     volume = {12},
     number = {2},
     doi = {10.4171/jems/202},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/jems/202/}
}