https://www.jabref.org/
JabRef - Free Reference Manager - Stay on top of your Literature
A free reference manager that helps you to discover, collect, organize and cite your scholarly literature and research in an efficient way.
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https://www.elsevier.com/en-au/products/mendeley
Mendeley | Free reference manager | Elsevier
Mendeley is a free reference manager that can help you store, organize, note, share and cite references and research data
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