Smith, Barry (1995). "On Drawing Lines on a Map". In Frank, A. U.; Kuhn, W.; Mark, D. M. (eds.). Spatial Information Theory. Proceedings of COSIT 1995. Berlin/Heidelberg/Vienna/New York/London/Tokyo: Springer Verlag. pp.475–484. Archived from the original on 2019-02-09. Retrieved 2017-01-03.
Smith, Barry (1995). "On Drawing Lines on a Map". In Frank, A. U.; Kuhn, W.; Mark, D. M. (eds.). Spatial Information Theory. Proceedings of COSIT 1995. Berlin/Heidelberg/Vienna/New York/London/Tokyo: Springer Verlag. pp.475–484. Archived from the original on 2019-02-09. Retrieved 2017-01-03.