B. Nasiri, A. Ennajih, A. Errkik, J. Zbitou, and M. Derri, “Coplanar band-pass filter for GSM applications based on novel metamaterial unit cell”, IJET, vol. 7, no. 4, pp. 6544–6546, Jun. 2019, doi: 10.14419/ijet.v7i4.28615.