IDEAS: Economics and Finance Research -
http://sciencebooksonline.info
Bartleby.com -
http://www.hawaii.edu/emailref/internet_resources/Books_and_Publishers.html
http://www.booksshouldbefree.com
http://oerconsortium.org/discipline-specific
http://collegeopentextbooks.org/textbooks/textbooksbysubject.html
http://www.e-booksdirectory.com
http://ebooks.adelaide.edu.au/meta/authors.html
http://www.flatworldknowledge.com
http://googlelittrips.com/GoogleLit/Home.html
http://www.archive.org/bookserver
http://www.fordham.edu/halsall
ipl2: Information You Can Trust -
http://quod.lib.umich.edu/m/moagrp
ManyBooks.net -
Open Culture -
Open Library -
Planet e-Book -
Safari Books Online -
http://proquest.safaribooksonline.com
Southern California Digital Library -
http://scdl.lib.overdrive.com/3ADF989E-99A7-438A-8166-77086A5FB966/10/393/en/Default.htm
TextbookRevolution -
http://www.textbookrevolution.org/index.php/Main_Page
The Critical Thinking Community -
http://www.criticalthinking.org
The Online Books Page: Archives and Indexes -
http://onlinebooks.library.upenn.edu/archives.html
Virtual Reference Shelf (Library of Congress) -
http://www.loc.gov/rr/askalib/virtualref.html
World Digital Library -
World Lecture Hall -
http://web.austin.utexas.edu/wlh