@article{10_1090_S0894_0347_2012_00754_1,
     author = {Ionescu, Alexandru and Klainerman, Sergiu},
     title = {On the local extension of {Killing} vector-fields in {Ricci} flat manifolds},
     journal = {Journal of the American Mathematical Society},
     pages = {563--593},
     publisher = {mathdoc},
     volume = {26},
     number = {2},
     year = {2013},
     doi = {10.1090/S0894-0347-2012-00754-1},
     url = {http://geodesic.mathdoc.fr/articles/10.1090/S0894-0347-2012-00754-1/}
}