1, Zhang Qiao Scientific Research

At present, there are 73,277,926 Chinese documents, and more than 26 million are updated every month. There are 539,265,438+0,990 articles in foreign languages, and more than 2 million articles are updated every month, including foreign periodicals, foreign conferences, foreign OA documents, foreign degrees: scientific and technological reports of the US government, and national defense scientific and technological reports of foreign troops.

2. Dspace of the Library of Hong Kong University of Science and Technology

Including academic papers, dissertations and research reports of the Hong Kong University of Science and Technology, the full text can be obtained free of charge.

3. Forgotten books

Forgotten Books is a London-based book publisher specializing in the renovation of old books, including novels and non-fiction works. There are 787,733 books available for online reading, or downloaded as e-books or purchased in writing.

4. Project Gutenberg

This is well known in academic circles. Gutenberg plans to provide more than 56,000 kinds of free e-books, which can be read or downloaded online for free without any fees or registration. Here, you will find great literature in the world, especially old works whose copyright has expired.

5. Database of Joint Journals of Developing Countries

Non-profit electronic publishing service organization, providing full-text of various open access periodicals in developing countries (such as Brazil, Cuba, India, Indonesia, Kenya, South Africa, Uganda, Zimbabwe, etc.). ).