@inproceedings{bridges2011:11,
  author      = {Gary R. Greenfield},
  title       = {Abstract Overlays using a Transport Network Model},
  pages       = {45--50},
  booktitle   = {Proceedings of Bridges 2011: Mathematics, Music, Art,
                 Architecture, Culture},
  year        = {2011},
  editor      = {Reza Sarhangi and Carlo H. S\'{e}quin},
  isbn        = {978-0-9846042-6-5},
  issn        = {1099-6702},
  publisher   = {Tessellations Publishing}
}