Liao , Hong-LinMcLean , William and Zhang , Jiwei. (2021). A Second-Order Scheme with Nonuniform Time Steps for a Linear Reaction-Subdiffusion Problem.
            <i>Communications in Computational Physics</i>. <i>30</i> (2).
            567-601.
         doi:10.4208/cicp.OA-2020-0124