Butt, Muhammad Ali, and Nikolai Lvovich Kazansky. “Narrowband Perfect Metasurface Absorber Based on Impedance Matching”. Photonics Letters of Poland 12, no. 3 (September 30, 2020): 88–90. Accessed April 28, 2024. https://www.photonics.pl/PLP/index.php/letters/article/view/12-30.