Directory

Visual literature-exploration tool that builds a similarity graph of papers around a seed paper, with prior and derivative works lists

Membership organization that registers DOIs for scholarly content and exposes the metadata through a free public REST API, content negotiation and the paid Metadata Plus service

Free scholarly search engine from Google that indexes articles, theses, books and court opinions with citation counts and author profiles

Free reference manager from Elsevier with a desktop and web app, PDF annotation, a Web Importer, groups and bundled cloud storage

Subscription reference manager that lives in the browser and Google Drive, with citation plugins for Google Docs and Word and mobile apps

Volunteer-run decentralized bibliographic database of economics research, fed by institutional archives and served through IDEAS, EconPapers, the Author Service, CitEc, NEP and MPRA

Literature-discovery app that grows collections of papers through citation and author networks and recommends related work, with a free-forever tier

Citation-analysis platform whose Smart Citations show whether later papers support, contrast or merely mention a claim, with an AI assistant and reference checking

Free AI-assisted literature search from Ai2 with an Academic Graph API, recommendations and downloadable datasets of papers, authors and citations