Gomes, Luiz H., Almeida, Rodrigo B., Bettencourt, Luis M. A., Almeida, Virgilio and Almeida, Jussara M. Comparative Graph Theoretical Characterization of Networks of Spam and Legitimate Email. (2005). .

Kong, Joseph S., Boykin, P. Oscar, Rezaei, Behnam Attaran, Sarshar, Nima and Roychowdhury, Vwani P.. "Scalable and Reliable Collaborative Spam Filters: Harnessing the Global Social Email Networks.." Paper presented at the meeting of the CEAS, 2005.

Golbeck, J. and Hendler, J. Reputation Network Analysis for Email Filtering. (2004). .

Gyöngyi, Zoltán, Garcia-Molina, Hector and Pedersen, Jan. "Combating Web Spam with TrustRank.." Paper presented at the meeting of the VLDB, 2004.