In the library's Volter database, there are plenty of Open Access resources indexed in the International articles (Primo) search (e.g. DOAJ).
In the Library's books, journals, databases search (SFX) there are, for example, the following Open Access journal resources:
Since the journals are in SFX it makes it easier to find them also when using other databases supporting SFX. It's also possible to add single OA journals to Volter as needed. Suggestions and requests may be communicated to firstname.lastname@example.org.
Volter's Primo search (the International Articles tab) also indexes international OA books, for example:
In the Library's books, journals, databases search there are, for example, the following OA books:
Single books can be added as needed (e.g. if they are course books or if the authors are from the University of Turku). Please send any suggestions to email@example.com.
Kopernio and Unpaywall in browser (click pictures to see bigger versions)
The Kopernio button appears down on the left and the Unpaywall button on the right side of the page. If a free version is found via Unpaywall, the lock logo is green and "open". The Kopernio button, instead, shows where and in which form the free version is found.
Both buttons can also be found on the tool bar/address bar. Here, the Kopernio search returns the results in Google Scholar. The Unpaywall button only shows if it has access to the current page or not.