Redirected from Umar
He succeeded Abu Bakr, the first caliph, and was succeeded by Uthman ibn Affan, the third caliph.
... Wittebol Post Hennekam syndrome[?] Autism Autoimmune hemolytic anemia[?] Autoimmune hepatitis[?] Autoimmune peripheral neuropathy[?] Autoimmune polyendocrinopathy ...