1. Eurordis 2006 What is a rare disease? Fact sheet http://www.eurordis.org/publication/what-rare-disease
2. MedlinePlus Website 2014 Rare diseases http://www.nlm.nih.gov/medlineplus/rarediseases.html
3. Global Genes website 2014 «RARE Facts and Statistics.» http://globalgenes.org/rarefacts/
4. ISEBOX Ltd/Shire 2014 Rare disease impact report http://www.rarediseaseimpact.com
5. Physician and patient perceptions regarding physician training in rare diseases: the need for stronger educational initiatives for physicians;Engel;Journal of Rare Disorders,2013