Atif Nazir Saqib Raza Chen-Nee Chuah Unveiling facebook: a measurement study of social network based applications. 43-56 2008 Internet Measurement Comference http://doi.acm.org/10.1145/1452520.1452527 conf/imc/2008 db/conf/imc/imc2008.html#NazirRC08