@inproceedings{bridges2009:243,
  author      = {Gailiunas, Paul},
  title       = {Concave Hexagons},
  pages       = {243--250},
  booktitle   = {Proceedings of Bridges 2009: Mathematics, Music, Art, Architecture, Culture},
  year        = {2009},
  editor      = {Kaplan, Craig S. and Sarhangi, Reza},
  isbn        = {978-0-96652-020-0},
  issn        = {1099-6702},
  publisher   = {Tarquin Publications},
  address     = {London},

  url         = {http://archive.bridgesmathart.org/2009/bridges2009-243.html}
}