Jianjiang Yu Kan-Jian Zhang Shumin Fei Tao Li Simplified exponential stability analysis for recurrent neural networks with discrete and distributed time-varying delays. 465-474 2008 205 Applied Mathematics and Computation 1 http://dx.doi.org/10.1016/j.amc.2008.08.022 db/journals/amc/amc205.html#YuZFL08