Gertjan J. Burghouts, Richard den Hollander, Klamer Schutte, Jan-Willem Marck, Sander Landsmeer, Eric den Breejen, "Increasing the security at vital infrastructures: automated detection of deviant behaviors," Proc. SPIE 8019, Sensors, and Command, Control, Communications, and Intelligence (C3I) Technologies for Homeland Security and Homeland Defense X, 80190C (2 June 2011);