Antony Galton.Lines of sight[A].Dorota Kieronska, AISB Workshop on Spatial and Spatio-temporal Reasoning[C].Berlin:Springer, 1994.1-15.
[2]
David R, etc.From images to bodies:Modeling and exploiting spatial occlusion and motion parallax[A].Bernhard Nebel, Proceedings of the17th IJCAI[C].San Francisco:Morgan Kaufmann Publishers, 2001.57-63.