Burke's Genealogical History of the Dormant, Abeyant, Forfeited @ Has her d. of Richard FitzJohn (her brother in this db)
The cited information was published by Burke's Peerage, London, 1866 (Ref: Has her d. of Richard FitzJohn (her brother in this db)) The author/originator was Burke's Peerage.
Source Notes
TITL Burke's Genealogical History of the Dormant, Abeyant, Forfeited
& Extinct Peerages of the British EmpireABBR Burke's Dormant Peerage