Keynes 2014, p. 16; Williams 1991a, p. 27; Costambeys 2004b. Keynes, Simon (2014). "Æthelred 'Lord of the Mercians' (d. 911)". In Lapidge, Michael; Blair, John; Keynes, Simon; Scragg, Donald (eds.). The Wiley Blackwell Encyclopaedia of Anglo-Saxon England (2nd ed.). Wiley Blackwell. p. 16. ISBN978-0-631-22492-1. Williams, Ann (1991a). "Æthelred Lord of the Mercians c. 883–911". In Williams, Ann; Smyth, Alfred P.; Kirby, D. P. (eds.). A Biographical Dictionary of Dark Age Britain. Seaby. p. 27. ISBN978-1-85264-047-7. Costambeys, Marios (2004b). "Æthelred (d. 911), ruler of the Mercians". Oxford Dictionary of National Biography. Oxford University Press. doi:10.1093/ref:odnb/52311. (subscription or UK public library membership required)
Keynes 2014, p. 16; Williams 1991a, p. 27; Costambeys 2004b. Keynes, Simon (2014). "Æthelred 'Lord of the Mercians' (d. 911)". In Lapidge, Michael; Blair, John; Keynes, Simon; Scragg, Donald (eds.). The Wiley Blackwell Encyclopaedia of Anglo-Saxon England (2nd ed.). Wiley Blackwell. p. 16. ISBN978-0-631-22492-1. Williams, Ann (1991a). "Æthelred Lord of the Mercians c. 883–911". In Williams, Ann; Smyth, Alfred P.; Kirby, D. P. (eds.). A Biographical Dictionary of Dark Age Britain. Seaby. p. 27. ISBN978-1-85264-047-7. Costambeys, Marios (2004b). "Æthelred (d. 911), ruler of the Mercians". Oxford Dictionary of National Biography. Oxford University Press. doi:10.1093/ref:odnb/52311. (subscription or UK public library membership required)