You can use a special search of ProQuest Dissertations & Theses to find full-text open-access dissertations, PQDT Open Access Dissertations. https://www.proquest.com/?accountid=13189
When the service opens, you should make two choices:
- Click the Dissertations & Theses button;
- And the Full Text checkbox;
- Then type your search terms.
The search results will be full-text dissertations that you can read or download immediately.
The Library's Online Resources A-Z pages also list this special service.