ArXiv
Physics, Mathematics, Computer Science, Quantitative Biology, Quantitative Finance and Statistics
DOAJ (Directory of Open Access Journals)
OPCIT (The Open Citation Project)
Project Euclid
DSpace MIT
MIT's digital research materials including an increasing number of conference papers, images, peer-reviewed scholarly articles, preprints, technical reports, theses, working papers, and more
NewJournals
HINARI, Health InterNetwork Access to Research Initiative,
Registry of Open Access Repositories (ROAR)
Directory of Open Access Repositories, (OpenDOAR)
Free Scientific Resources
Directory of Open Access Journals
Regional Information Center for Science & Technology
Free Resources
TIFR-CAM Library
List of Free Online Full Text Journals in Mathematics
MathWorld
Math-Net
Digital Library of Mathematical Functions
Department of Mathematics at the College of Charleston
Macalester College Problem of the Week
Mathematical Atlas
EMIS: The European Mathematical Information Service
KTH
E-math of AMS
Mathematical Journals of University of Wisconsin - Whitewater
MagIrn
Mathematical Science Publishers
The Psychonomic Society
Scientific Research in Psychology and Allied Sciences, Founded 1959
Free Journals
Advances in Natural Sciences: Nanoscience and Nanotechnology
Distributed Systems Engineering
IOP Conference Series: Materials Science and Engineering
Journal of High Energy Physics
Journal of Physics: Conference Series
New Journal of Physics
Science and Technology of Advanced Materials
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AMS Books Online
Banach Center Publications
ICTP Lecture Notes