* The History Files: In the Footsteps of Ivarr the Boneless* A site on the disease Osteogenesis Imperfecta* Northvegr – "The Tale of Ragnar's Sons"* Nabil Shaban's page about Ivar the Boneless* An article discussing the OI theory
==External links==* The History Files: In the Footsteps of Ivarr the Boneless*A site on the disease Osteogenesis Imperfecta*Northvegr – "The Tale of Ragnar's Sons"*Nabil Shaban's page about Ivar the Boneless*An article discussing the OI theory