* limits of identity knowledge? - http://www.economist.com/sciencetechnology/displaystory.cfm?story_id=13176775
* saccade eye motion profile http://www.liv.ac.uk/~pcknox/teaching/Eymovs/params.htm
[Img src="http://www.liv.ac.uk/~pcknox/teaching/Eymovs/sacpar.gif"]