@article{mandal_das_2013,  title={Microstrip feed spanner shape monopole antennas for ultra wide band applications},  volume={12},  ISSN={2179-1074},  url={https://doi.org/10.1590/S2179-10742013000100002},  DOI={10.1590/S2179-10742013000100002},  number={1},  journal={Journal of Microwaves, Optoelectronics and Electromagnetic Applications},  publisher={Sociedade Brasileira de Microondas e Optoeletrônica e Sociedade Brasileira de Eletromagnetismo},  author={Mandal, Tapan and Das, Santanu},  year={2013},  month={Jun},  pages={15–22} }