1. http://www.ncvhs.hhs.gov/nhiilayo.pdf (accessed 22 Aug 2010).
2. HHS Secretary Tommy. Thompson Launches ‘Decade of Health Information Technology.’ http://www.archive.hhs.gov/news/press/2004pres/20040721a.html (accessed 21 Feb 2011).
3. Interoperability: the key to the future healthcare system;Brailer;Health Aff (Millwood),2005
4. http://www.ehealthinitiative.org/members-download/finish/4-open/35-hie-survey-report-2010-key-findings.html (accessed 22 Aug 2010).
5. http://www.healthit.hhs.gov/portal/server.pt/gateway/PTARGS_0_10731_848093_0_0_18/summary_report_on_nhin_Prototype_architectures.pdf (accessed 22 Aug 2010).