Huiqin Chen Jinqiao Duan Xiaofan Li 0003 Chengjian Zhang A computational analysis for mean exit time under non-Gaussian Lévy noises. 1845-1856 2011 218 Appl. Math. Comput. 5 https://doi.org/10.1016/j.amc.2011.06.068 db/journals/amc/amc218.html#ChenDLZ11