1. White Paper 2011 Information & Communications in Japan, Part 1, Section 1http://www.soumu.go.jp/johotsusintokei/whitepaper/eng/WP2011/2011-index.html
2. White Paper 2011 Information & Communications in Japan, Part 1, Chapter 3http://www.soumu.go.jp/johotsusintokei/whitepaper/eng/WP2012/2012-index.html
3. Delay Tolerant Networks (DTNs)—A Tutorial Version 2.0. Warthman Associates, Based on Technology Developed by the Interplanetary Internet Special Interest Grouphttp://ipnsig.org/wp-content/uploads/2012/07/DTN_Tutorial_v2.04.pdf
4. Epidemic Routing for Partially-Connected Ad Hoc Networks;Vahdat,2000