|SOME NOTES ON MEDIEVAL ENGLISH GENEALOGY|
Volume 12, part 2, page 168, note g:
His [Hugh de Lacy's, Earl of Ulster (d. 1242)] sisters were ... (iii) (----), m. William FitzAlan.
This was William FitzAlan, lord of Clun and Oswestry (d. c.1210). See FitzAlan (of Oswestry), vol.5, p.391.