Books and Journals
As of 2010, there were over 15 million books on Google Books. Many of the books, if a book is out of copyright or the publisher has given permission to Google, are available for preview or full-text. If the book is in the public domain, a PDF copy is free to download.
WorldCat is the world's largest network of library content and services.
DOAJ is a free, full-text quality controlled directory which provides access to a variety of journals covering all disciplines. Journals are available in languages other than English. To view journals in a specific field, Browse the databases.
The INASP provides a directory of free and open access online resources. Coverage includes the following disciplines: agriculture, biology & life science, chemistry, earth sciences, engineering & technology, environment, humanities, information & communication technologies, mathematics & statistics, medicine & health sciences, physics, and social sciences.
The NAP publishes more than 200 books a year on a wide range of topics in science, engineering, and medicine, providing authoritative information on important matters in science and health policy.
OpenDOAR is an authoritative directory of academic open access repositories.