เกื้อทวีกุ เ. (2015) “Bandwidth Enhancement Techniques of Slot Antenna CPW-Fed for Wireless Communication Systems”, Frontiers in Engineering Innovation Research, 1, pp. 43–54. available at: https://ph01.tci-thaijo.org/index.php/jermutt/article/view/242055 (accessed: 15 June 2025).