Books
Raphael Holinshed, Chronicles of England, Scotland and Ireland: England.- v. 5. Scotland.- v. 6 Ireland, 1808, J. Johnson. E-book.
Nick Aitchison, Macbeth Man and Myth, 1999, Stroud, Gloucestershire, Sutton Publishing Limited. Book.
Jonathan Clements, A Brief History of the Vikings, 2005, London, Constable & Robinson Ltd. E-book.
Cameron Taylor, Alistair Murray, On the Trail of the Real Macbeth, King of Alba, 2008, Edinburgh, Luath Press Limited. E-book (2015)
Laurence Larson, Canute the Great, 2016, Ozymandias Press.
Richard Abels, Aethelred the Unready, The Failed King, 2018, Renguin Random House, UK. E-book.
Podcast
Websites
https://www.historytoday.com/archive/st-brice%E2%80%99s-day-massacre
https://www.jstor.org/stable/25529143?seq=1
https://historica.fandom.com/wiki/Siege_of_Durham_(1006)
Wikipedia
I use Wikipedia mostly to quickly check or verify dates, find links to source texts, and see additional information in various languages, I find a lot of information is inaccurate, outdated, or incomplete. Use Wikipedia with caution, kids!
https://en.wikipedia.org/wiki/Battle_of_Carham
https://en.wikipedia.org/wiki/St._Brice%27s_Day_massacre
https://en.wikipedia.org/wiki/Sweyn_Forkbeard
https://en.wikipedia.org/wiki/Sigurd_the_Stout
https://en.wikipedia.org/wiki/Thorfinn_the_Mighty
YouTube
Video about the Battle of Carham, 1018. https://www.youtube.com/watch?v=YyzSXqxKUnE