William de [Baron Ferrers] Ferrers - Pedigree | FamilyCentral
 30 Jan 1271/72 - 20 Mar 1324/25
 Abt 1240 - 20 Dec 1287
 Abt 1248 -
 Bef 1223 - 4 Aug 1265
 1241 - Bef 11 Apr 1281