@article{articlec770d302,
title   = {Isometric immersions into a homogeneous Lorentzian Heisenberg group and rigidity},
author = {Lodovici, Sinuê Dayan Barbero and Manfio, Fernando},
year = {2009},
doi = {10.1017/s0305004109002308},
journal   = {Mathematical Proceedings of the Cambridge Philosophical Society}
}