1. The Napster homepage.
https://en.wikipedia.org/wiki/Napster
. Accessed 11 May 2019.
2. Open Source Community. The free network project - rewiring the internet.
http://freenet.sourceforge.net/
. Accessed 13 Aug 2019.
3. https://en.wikipedia.org/wiki/Gnutella
. Accessed 13 Aug 2019.
4. BitTorrent.
http://www.bittorrent.com/
. Accessed 13 Aug 2019.
5. Hari, B., Frans, M., & David, K. (2003). Looking up data in P2P system. Communication of the ACM,46, 43–48.