Anselm, Saint Archbishop of Canterbury. [Letter to Athelits, abbess of St. Mary at Romsey, 1102] in Sancti Anselmi Cantuariensis Archiepiscopi Opera Omnia 4.144-45

[Letter from Anselm, archbishop of Canterbury to Athelits, abbess of St. Mary at Romsey]
Archbishop Anselm reprimands the abbess and her nuns for asking his advice and then disobeying him by continuing to worship the Anglo-Saxon Earl Waltheof, who had been executed for treason, as a martyr and saint. He wrote to Stephen (ep.236), archdeacon of Winchester, at the same time, commanding him to go to the abbess and tell her and the nuns that they will be put under interdict unless they prevent any worship of the Earl who had presumably been their patron.
Online at Epistolae (See also Bibliographia record).