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By Alain Barrat, Marc Barthelemy. Alain Barrat is a Senior Researcher at the Laboratoire de Physique Theorique (CNRS and Universite de Paris-Sud, France), and the Complex Networks Lagrange Laboratory at the Institute for Scientific Interchange in Turin, Italy.
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.