books.google.by - Monthly in cities around the world, bicyclists take over the streets in an "organized coincidence" called Critical Mass. Riding along several hundred strong, hooting and hollering, whistling, laughing and singing; it is a coup on wheels, a clever tactical strike against our oil-dependent culture. Containing...http://books.google.by/books/about/Critical_mass.html?id=iVpHsLMgiCcC&utm_source=gb-gplus-shareCritical mass
