Towrie, Sigurd (c. 2011). "Brodgar Boy". Orkneyjar.com. The Ness of Brodgar Trust. Archived from the original on 6 August 2016. Retrieved 8 March 2018.
(Towrie?), Sigurd (7 August 2013). "Wednesday, August 7, 2013". Orkneyjar.com. Excavation Diary. The Ness of Brodgar Trust. Archived from the original on 25 March 2014. Retrieved 12 July 2016.
Towrie, Sigurd (c. 2011). "Brodgar Boy". Orkneyjar.com. The Ness of Brodgar Trust. Archived from the original on 6 August 2016. Retrieved 8 March 2018.
(Towrie?), Sigurd (7 August 2013). "Wednesday, August 7, 2013". Orkneyjar.com. Excavation Diary. The Ness of Brodgar Trust. Archived from the original on 25 March 2014. Retrieved 12 July 2016.