Liu , MinXu , LipingLi , Zhi and Chen , Zhong. (2017). Harnack Inequality and Applications for Stochastic Retarded Differential Equations Driven by Fractional Brownian Motion.
            <i>Journal of Partial Differential Equations</i>. <i>30</i> (1).
            84-94.
         doi:10.4208/jpde.v30.n1.7