Akshay Java Xiaodan Song Tim Finin Belle L. Tseng Why We Twitter: An Analysis of a Microblogging Community. 118-138 2007 WebKDD/SNA-KDD http://dx.doi.org/10.1007/978-3-642-00528-2_7 conf/kdd/2007web db/conf/kdd/webkdd2007.html#JavaSFT07