Citavi
Reference management plus knowledge organization — think, then write.
Tier 3 ToolsFreemium
Research Database Directory
Every research database, reviewed.
DataCite
DOIs for data — the identifier registry that makes datasets citable.
Tier 3 ToolsFree
ORCID
A unique ID for every researcher — the thread that ties a career's work together.
Tier 2 ToolsFree
ROR
A persistent ID for every research organization — ORCID for institutions.
Tier 3 ToolsFree
PubPeer
Post-publication peer review — where the community flags what the journals missed.
Tier 3 ToolsFree
Unpaywall
The one-click route to a legal free version of almost any paper.
Tier 2 ToolsFree
Open Science Framework (OSF)
The open-science workbench — manage a project, preregister, and share it all.
Tier 2 ToolsFree
WorldCat
The union catalog of the world's libraries — find who holds a book or item, and where.
Tier 2 ToolsFree
Crossref
The DOI backbone of scholarly publishing — metadata that ties the literature together.
Tier 2 ToolsFree
Mendeley
Elsevier's reference manager and academic network — capable, if you accept the ecosystem.
Tier 3 ToolsFree