It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.
Grey Literature: General resources
What is grey literature, why should you use it, how do you find it?
Provides more than 240 million documents from more than 8,000 content providers. You can access the full texts of about 60% of the indexed documents for free (Open Access). BASE is operated by Bielefeld University Library.’
Core is the world’s largest collection of open access full texts. Open access research papers from repositories and open access journals. 219,218,877 full texts. Also has a browser extension, Core Discovery https://core.ac.uk/services/discovery
Access to bibliographic references of grey literature from Europe. Grey literature includes technical and research reports, doctoral dissertations, some conference proceedings and some official publications.
Open access/freely available content. No login required.