@article{Kannappan03,
  title = {Klee's Trigonometry Problem},
  author = {Palaniappan Kannappan},
  year = {2003},
  url = {http://www.jstor.org/stable/3647966},
  researchr = {https://researchr.org/publication/Kannappan03},
  cites = {0},
  citedby = {0},
  journal = {The American Mathematical Monthly},
  volume = {110},
  number = {10},
  pages = {940-944},
}