2012 Ninth International Conference on Information Technology - New Generations. French streets also handle substantial worldwide site visitors, connecting with metropolitan areas in neighbouring Belgium, Luxembourg, Germany, Switzerland, Italy, Spain, Andorra and Monaco. Stone-Gross, B. Holz, T. Stringhini, G. Vigna, G. (2011). "The Underground Economy of Spam: A Botmaster's Perspective of Coordinating Large-Scale Spam Campaigns" (PDF).