\bibitem{DalTREC05spam} Vlado Ke\v{s}elj, Evangelos Milios, Andrew Tuttle, Singer Wang, and Roger Zhang. \newblock {DalTREC} 2005 Spam Track: Spam Filtering using N-gram-based Techniques. \newblock In {\em The Fourtheenth Text REtrieval Conference (TREC 2005) Proceedings\/.} Gaithersburg, Maryland, USA, November 2005.