Raj Talluri J. K. Aggarwal Edge Visibility Regions - A New Representation of the Environment of a Mobile Robot. 375-380 1990 MVA http://b2.cvl.iis.u-tokyo.ac.jp/mva/proceedings/CommemorativeDVD/1990/papers/1990375.pdf conf/mva/1990 db/conf/mva/mva1990.html#TalluriA90