I suppose the article is referring to the SOSTOOLS (where SOS = <i>Sum of Squares</i>) free MATLAB toolbox:<p><a href="http://www.cds.caltech.edu/sostools" rel="nofollow">http://www.cds.caltech.edu/sostools</a><p><a href="http://www.mit.edu/~parrilo/sostools" rel="nofollow">http://www.mit.edu/~parrilo/sostools</a><p>The article could have mentioned that more people have worked on this. The whole thing started while Parrilo and Prajna were Prof. John Doyle's grad students at Caltech / CDS. Yet once again, MIT's shameless self-promotion fails to give credit where credit is due...