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This is the original article from the IEEE 'Computer' journal. Also interesting is this [paper](http://informatik.unibas.ch/fileadmin/Lectures/HS2012/CS341/workshops/reportsAndSlides/ReportKevinUrban.pdf) and [slides](http://informatik.unibas.ch/fileadmin/Lectures/HS2012/CS341/workshops/reportsAndSlides/PresentationKevinUrban.pdf) by Kevin Urban discussing the article.