Zhang, B. ., X. . Xu, X. . Deng, Y. . Wang, and J. . Wei. “Stacked Metamaterial Patch Antenna Made of Low Permittivity Dielectrics”. Applied Computational Electromagnetics Society Journal (ACES), vol. 37, no. 06, June 2022, pp. 743-9, doi:10.13052/2022.ACES.J.370610.