Guo , YichenJia , LuelingChen , HuajieLi , Huiyuan and Zhang , Zhimin. (2021). A Mortar Spectral Element Method for Full-Potential Electronic Structure Calculations.
            <i>Communications in Computational Physics</i>. <i>29</i> (5).
            1541-1569.
         doi:10.4208/cicp.OA-2020-0020