Yang, Qian, Shuangyang Liu, Kai-Da Xu, and Anxue Zhang. “Compact Octa-Band Bandpass Filter Based on Controllable Transmission Zeros With Wide Upper Stopband”. Applied Computational Electromagnetics Society Journal (ACES) 36, no. 09 (November 6, 2021): 1159–1163. Accessed July 14, 2024. https://journals.riverpublishers.com/index.php/ACES/article/view/12129.