NameÆlfgifu, 29G Grandmother
Web Notes notes for Ælfgifu
Debrett's Kings and Queens of Britain" by David Williamson, ISBN 0-86350-101-X, p. 30:
Canute had a mistress, Elfgiva, daughter of Elfhelm, Ealdorman of Northampton, and they had two sons. Soon after his accession he repudiated her although she was a very able woman and later governed Norway with her son Sweyn.