Gujjula , Vaishnavi and Ambikasaran , Sivaram. (2022). A New Directional Algebraic Fast Multipole Method Based Iterative Solver for the Lippmann-Schwinger Equation Accelerated with HODLR Preconditioner.
            <i>Communications in Computational Physics</i>. <i>32</i> (4).
            1061-1093.
         doi:10.4208/cicp.OA-2022-0103