Google Scholar
Google Scholar provides a simple way to broadly search for scholarly literature. From one place, you can search across many disciplines and sources: articles, theses, books, abstracts and court opinions, from academic publishers, professional societies, online repositories, universities and other web sites. Google Scholar helps you find relevant work across the world of scholarly research.
Cambridge University Press Open Access
Open access journals from Cambridge University Press
JSTOR Open Access Journals
A growing collection of Open Access journals cover topical areas in sustainability and security studies, and offer broad coverage in the humanities, social sciences, and sciences.
Sage Open Access Journals
Open access journals published by SAGE. All articles published in the journals provide worldwide, barrier-free access to the full-text of articles online, immediately on publication under a creative commons license.
The Internet Archive
The Internet Archive offers over 20,000,000 freely downloadable books and texts. There is also a collection of 2.3 million modern eBooks that may be borrowed by anyone with a free archive.org account.
WorldCat.org
WorldCat.org lets you search the collections of libraries in your community and thousands more around the world. You can search for popular books, music CDs and videos—all of the physical items you're used to getting from libraries. You can also discover many new kinds of digital content, such as downloadable audiobooks. You may also find article citations with links to their full text; authoritative research materials, such as documents and photos of local or historic significance; and digital versions of rare items that aren't available to the public. Because WorldCat libraries serve diverse communities in dozens of countries, resources are available in many languages.
Frontiers
Frontiers is a leading Open Access Publisher and Open Science Platform. Our journals are led and peer-reviewed by editorial boards of over 100,000 top researchers. Covering more than 600 academic disciplines, we are one of the largest and highest-cited publishers in the world. To date, our freely accessible research articles have received over 500 million views and downloads and 1 million citations.
Nature Communications
Nature Communications is an open access, multidisciplinary journal dedicated to publishing high-quality research in all areas of the biological, health, physical, chemical and Earth sciences. Papers published by the journal aim to represent important advances of significance to specialists within each field.
National Center for Biotechnology Information
Bookshelf provides free online access to books and documents in life science and healthcare
PLOS ONE
PLOS ONE is an inclusive journal community working together to advance science for the benefit of society, now and in the future. The research we publish is multidisciplinary and, often, interdisciplinary. PLOS ONE accepts research in over two hundred subject areas across science, engineering, medicine, and the related social sciences and humanities. We evaluate submitted manuscripts on the basis of methodological rigor and high ethical standards, regardless of perceived novelty.
Science Direct Open Access
Open access journals and books from Science Direct.
Science.gov
Science.gov makes it possible for users to search over 60 databases, over 2,200 websites, and over 200 million pages of authoritative federal science information in many formats, including full-text documents, citations, scientific data supporting federally funded research, and multimedia.