Chao Liu Zhisheng Duan Guanrong Chen Lin Huang L<sub>2</sub> norm performance index of synchronization and LQR control synthesis of complex networks. 1879-1885 2009 45 Automatica 8 http://dx.doi.org/10.1016/j.automatica.2009.04.004 db/journals/automatica/automatica45.html#LiuDCH09