arXiv is an open access database of over 1,757,455 scholarly articles in the fields of physics, mathematics, computer science, quantitative biology, quantitative finance, statistics, electrical engineering and systems science, and economics. Materials on this site are not peer-reviewed by arXiv. Check out the math specific section to see what areas this resource covers.
The Smithsonian Astrophysical Observatory/U.S. National Aeronautics and Space Administration (SAO/NASA) Astrophysics Data System (ADS) is a searchable database of article and conference proceeding abstracts in the fields of Physics and Astronomy. Linked to the arXive article database, or open access versions of papers. UNLV community members may also link to UNLV's subscriptions and interlibrary loan by creating a personal account and selecting "University of Nevada" in the Library Links Settings preferences