1. http://www.alopeciaareata.com
2. http://www.ehrs.org
3. References
4. Alopecia areata: a statistical study and consideration of endocrine influences;Walker;J Invest Dermatol,1950
5. Alopecia areata. A follow-up investigation of outpatient material;Gip;Acta Derm Venereol (Stockh),1969