H. M. Abdul-jabbar, T. A.-H. Naji, A. J. Hatem, and I. M. A. Abdul-Ameer, “Studying Hueckel Edge Detector Using Binary Step Edge Image”, IHJPAS, vol. 30, no. 1, pp. 20–28, Jun. 2017, doi: 10.30526/30.1.1056.