See, C. H., Abd-Alhameed, R. A., Zhou, D., Lee, T. H., & Excell, P. S. (2010). A Crescent-Shaped Multiband Planar Monopole Antenna for Mobile Wireless Applications. IEEE Antennas and Wireless Propagation Letters, 9, 152-155. https://doi.org/10.1109/lawp.2010.2044741