Blood Royal: Issue of the Kings and Queens of Medieval England 1066-1399: The Normans and Plantagenets @ 42-43
The cited information was published by Heritage Books, 1996 (Ref: 42-43) The author/originator was T. Anna Leese.
Blood Royal: Issue of the Kings and Queens of Medieval England 1066-1399: The Normans and Plantagenets.