Gaosheng Li, Gui Gao, Li-an Bian, Zhonghao Lu, and Chaoyun Song. “A Tunable Antenna With the Combination of Two Kinds of Liquid Materials”. Applied Computational Electromagnetics Society Journal (ACES), vol. 32, no. 11, July 2021, pp. 966-73, https://journals.riverpublishers.com/index.php/ACES/article/view/9427.