: A completely legal resource that indexes high-quality, peer-reviewed, open-access journals across all areas of science and technology.
: Similar to Unpaywall, it helps users find legal, free versions of research articles that are behind paywalls. Specialized Academic Search Engines
: A Chrome extension that finds the DOI of a paper on your current page and automatically searches for it across various open-access repositories like ArXiV and the Internet Archive .
: These platforms collectively offer over 10 million books and 85 million articles.
For discovering these papers, the following search engines are highly effective: Google Scholar Semantic Scholar CORE Baidu Scholar The best academic search engines [Update 2025] - Paperpile
: A legal tool that harvests open-access content from over 50,000 publishers and repositories, providing access to roughly 20 to 55 million scholarly articles.
