He [John de Hastinges] married, 1stly, at Braxted, Essex, or Blunham, Beds, Isabel, daughter of William DE VALENCE, sometimes styled EARL OF PEMBROKE, by Joan, daughter of Sir Warin DE MUNCHANESY, of Swanscombe, Kent, Winfarthing and Gooderstone, Norfolk, &c. She died 5 October 1305, and was buried in Coventry Priory. [Complete Peerage VI:346-9, XIV:372, (transcribed by Dave Utzinger)]