Qiao , Zhonghua and Zhang , Qian. (2022). Two-Phase Image Segmentation by the Allen-Cahn Equation and a Nonlocal Edge Detection Operator.
            <i>Numerical Mathematics: Theory, Methods and Applications</i>. <i>15</i> (4).
            1147-1172.
         doi:10.4208/nmtma.OA-2022-0008s