1. http://followerwonk.com/
2. https://blog.twitter.com/2012/shutting-down-spammers
3. https://blog.twitter.com/2010/state-twitter-spam
4. Amleshwaram, A.A., Reddy, A.L.N., Yadav, S., Gu, G., Yang, C.: Cats: characterizing automation of twitter spammers. In: COMSNETS, pp. 1–10. IEEE (2013)
5. Benevenuto, F., Magno, G., Rodrigues, T., Almeida, V.: Detecting spammers on twitter. In: Annual Collaboration, Electronic messaging, Anti-Abuse and Spam Conference (CEAS) (2010)