Margaret Cormack, 'Saints, Seals, and Demons: The Stories of Selkolla', in Supernatural Encounters in Old Norse Literature and Tradition, ed. by Daviel Sävborg and Karen Bek-Pedersen, Borders, Boundaries, Landscapes, 1 (Turnhout: Brepols, 2018), pp. 75-103 doi:10.1484/M.BBL-EB.5.116081; ISBN978-2-503-57531-5.
