Mendeley is a desktop and web program for managing and sharing research papers, discovering research data and collaborating online
Zotero is a free, easy-to-use tool to help you collect, organize, cite, and share your research sources.
EasyBib.com provides citation, note-taking and research tools. EasyBib offers free and premium services for individuals and institutions.
Find, use and share research with EndNote. It’s for more than bibliographies. Sync your EndNote library across your desktop, iPad and online. Work on your research from anywhere.
It offers a robust cross-platform suite of reference management & discovery tools that can dramatically improve the way researchers find, access, organize, read, annotate, share, and cite research literature
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