(IMAGE) Universidad Carlos III de Madrid Caption A study at the Universidad Carlos III de Madrid (UC3M) analyzes how social networks were used between the attacks on March 11, 2004 (11M) and the demonstration in the Puerta del Sol on May 15th (15M). Credit uc3m Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.