@article{JEMS_2016_18_9_a5,
     author = {Enrico Serra and Paolo Tilli},
     title = {A minimization approach to hyperbolic {Cauchy} problems},
     journal = {Journal of the European Mathematical Society},
     pages = {2019--2044},
     publisher = {mathdoc},
     volume = {18},
     number = {9},
     year = {2016},
     doi = {10.4171/jems/637},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/jems/637/}
}