access 160+ million publications and connect with 25+ million researchers. join for free and gain visibility by uploading your research.

internet archive is a non-profit digital library offering free universal access to texts, movies & music, as well as 624 billion archived web pages.

quillbot's paraphrasing tool is trusted by millions worldwide to rewrite sentences, paragraphs, or articles using state-of-the-art ai.

library genesis is a scientific community targeting collection of books on natural science disciplines and engineering.

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mdpi is a publisher of peer-reviewed, open access journals since its establishment in 1996.

proceedings of the national academy of sciences (pnas), a peer reviewed journal of the national academy of sciences (nas) - an authoritative source of high-impact, original research that broadly spans the biological, physical, and social sciences.

Semantic Scholar uses groundbreaking AI and engineering to understand the semantics of scientific literature to help Scholars discover relevant research.

NASA.gov brings you the latest news, images and videos from America's space agency, pioneering the future in space exploration, scientific discovery and aeronautics research.