Academia.edu - Academia is a website where you can share papers that are written with other users. You can use a Google or Facebook account to sign in to the website.
Crossref - Crossref makes research outputs easy to find, cite, link, assess, and reuse. We’re a not-for-profit membership organization that exists to make scholarly communications better.
Mendeley - Easily organize your papers, read & annotate your PDFs, collaborate in private or open groups, and securely access your research from everywhere.
Zotero - Zotero is a free, easy-to-use tool to help you collect, organize, cite, and share research.
Cabri Express - Cabri Express is an all-in-one math toolkit that facilitates the teaching and learning of mathematics from hight school to university
Google Scholar - Google Scholar is a freely accessible web search engine that indexes the full text of scholarly...