- Math Reviews: AMS database of more than a million reviews and abstracts of math publications (requires subscription).
ArXiv - - Open e-print archive with over 100,000 articles in physics, 10,000 in mathematics, and 1,000 in computer science. (Formerly called xxx; free.
Committee on Electronic Information Communication (CEIC) - - Part of the International Mathematical Union. Its mandate is to coordinate world-wide efforts to publish mathematical papers, journals, and other scholarly work in web form. It may recommend standards on issues related to electronic communication.
The Electronic Library of Mathematics - - The Electronic Library of Mathematics is offered by the European Mathematical Society (EMS) in cooperation with FIZ Karlsruhe / Zentralblatt MATH. Online journals, article collections, and monographs in electronic form: access is free.
EMANI - - Electronic Mathematical Archiving Network Initiative: to support the long-term electronic preservation of mathematical publications.
e-Math for Africa - - Coordinating efforts to make an African consortium for e-journals and databases. Includes 300+ links to open access math e-journals.
Fachinformationszentrum Karlsruhe (FIZ) - - Information services for academic and industrial research. Access to MATH Database (Zentralblatt für Mathematik), International Reviews on Mathematical Education (Zentralblatt für Didaktik der Mathematik), CompuScience and index to Springer Lecture Notes in CS.
Journal Copyright Policy Gossip - - Information from authors and publishers about the copyright policies of certain journals, maintained by William Stein.
JSTOR - - Scans of print journals, with 10 major math journals (requires subscription).
MathDiss International - - A project sponsored by the German Research Foundation to set up an international online full-text archive for mathematical theses in LaTeX format.
Mathematical Errata - - A growing collection of mathematical errata, corrections, and addenda to textbooks, monographs, and journal articles.
MR Lookup - - Bibliographic data from Math Reviews without the reviews (free).
ZMATH: Zentralblatt für Mathematik - - European database of reviews and abstracts of math publications. Requires subscription, but has limited free access.
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