@article{shen:1981:ma,
    author = {Shen, L.},
     title = {The elliptical microstrip antenna with circular polarization},
   journal = {IEEE Trans. Antennas and Propagation},
    volume = {29},
      year = {1981},
    number = {1},
     pages = {90–94},
     links = {\URL[FullText]{http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?tp=&arnumber=1142545&isnumber=25612}}}