You will need:
Author’s surname, Initials. (Year submitted) Title of dissertation/thesis. Level of award, Location of awarding institution if not clear from name: Name of awarding institution. Available from: www.webaddress.com [Accessed day month year].
Shelton, L. (2020) 'Small hands do them because they must' : examining the reception of 'The Lord of the Rings' among young readers. PhD Thesis, University of Glasgow. Available from: https://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.806281 [Accessed 17 February 2021].
In-text citation: (Levene, 2019)