@article{articleefc6decc,
title   = {Stability and instability of periodic travelling wave solutions for the critical Korteweg-de Vries and nonlinear Schrodinger equations},
author = {Pava, Jaime Angulo and Natali, Fabio M. Amorim},
year = {2009},
doi = {10.1016/j.physd.2008.12.011},
journal   = {Physica D-Nonlinear Phenomena}
}