PubMed Central
full text scientific/health research
Tools & resources
Digital Commons Network
free open access academic research
Open content on JSTOR
open access and free academic content/research on JSTOR
Directory of Open Access Books
directory of open access academic books and research
Directory of Open Access Journals
index of open access journals and articles
BASE (Bielefeld Academic Search Engine)
search engine for open access academic resources and information
Open Access Theses and Dissertations
search engine for open access graduate theses and dissertations