Other minor sources
Calendars of Abbey of Ely, Winchester and Ramsey
The calendar of Ely, which Brihtnoth had close associations, gives the 10th August, the currently accepted date, while the other two give 11th August for Brihtnoth’s death and hence for the battle.
John of Worcester and Symeon of Durham
Both just record that the battle took place in 991 and that Brihtnoth was killed along with many from both armies.
McGurk. The chronicle of John of Worcester, Oxford medieval texts, Oxford, Clarendon Press, 1998
Rollason. Libellus de exordio atque procursu istius, hoc est Dunhelmensis, ecclesie: Tract on the origins and progress of this the Church of Durham, Oxford medieval texts, Oxford, Oxford University Press 2000, 2000
Henry of Huntingdon
‘Ealdorman Brihtnoth indeed opposed them with great forces and fought them, but was defeated. He was killed, cut down by swords, and his troops were driven back and destroyed.’
For Henry of Huntingdon see:
Forester. The chronicle of Henry of Huntingdon, comprising the history of England, from the invasion of Julius Caesar to the accession of Henry II, Felinfach, Llanerch, 1991