XiaoLong, Wang, and Chen CuiXia. “An Automatic Ship Detection Method Based on Local Gray-Level Gathering Characteristics in SAR Imagery”. ELCVIA: Electronic Letters on Computer Vision and Image Analysis, vol. 12, no. 1, Sept. 2014, pp. 33-41, https://raco.cat/index.php/ELCVIA/article/view/280901.