• DIRECTORY OF OPEN ACCESS BOOKS (DOAB):This is an open-access directory of books covering all subjects in many languages. Areas include Agriculture and Food Sciences, Arts and Architecture, Biology and Life Sciences, Business and Economics, Chemistry, Earth and Environmental Sciences, General Works, Health Sciences, History and Archaelogy, Languages and Literature, Law and Political Science, Mathematics and Statistics, Philosophy and Religion, Physics and Astronomy, Science General, Social Sciences, Technology, and Engineering.
• ENCYCLOPEDIA BRITANNICA (Academic Edition): Animals, Art and Music, Astronomy, Biological Sciences, Chemistry, Countries of the World, Earth and Geography, Government, Law and Politics, Health and Medicine, History, Life and the Biosphere, Literature, Mathematics, Philosophy, Physics, Plants, Religion, Society, Sports and Recreation, Technology.
• INTECHOPEN: A directory of books ranging from Archeology to Zoology. Prominent among them are Health Sciences, Food Sciences, Biology and Life Sciences, Business and Economics, Chemistry, Earth and Environmental Sciences, Languages and Literature, Law and Political Science, Mathematics and Statistics, Philosophy and Religion, Physics and Astronomy, Science General, Social Sciences, Technology and Engineering, and Computer Science.
• MEDICAL AND NURSING BOOKS: Medical and Nursing textbooks, journals on Health Science.
• OAOPEN: A directory of books ranging from Archeology to Zoology. Prominent among them are Health Sciences, Food Sciences, Biology and Life Sciences, Business and Economics, Chemistry, Earth and Environmental Sciences, Languages and Literature, Law and Political Science, Mathematics and Statistics, Philosophy and Religion, Physics and Astronomy, Science General, Social Sciences, Technology and Engineering, and Computer Science.
• OPEN EDITION BOOKS: Books covering all subjects in many languages. Areas include Health Sciences, Agriculture and Food Sciences, Biology and Life Sciences, Business and Economics, Chemistry, Earth and Environmental Sciences, General Work, History and Archaeology, Languages and Literature, Law and Political Science, Mathematics and Statistics, Philosophy and Religion, Physics and Astronomy, Science General, Social Sciences, Technology, and Engineering.
• PDF DRIVE: A directory of books ranging from Archeology to Zoology. Prominent among them are Health Sciences, Food Sciences, Biology and Life Sciences, Business and Economics, Chemistry, Earth and Environmental Sciences, Languages and Literature, Law and Political Science, Mathematics and Statistics, Philosophy and Religion, Physics and Astronomy, Science General, Social Sciences, Technology and Engineering, and Computer Science.
• PROJECT GUTENBERG: Project Gutenberg is a multidisciplinary E-book database. It is recognized as the oldest digital library in the world.
• PROJECT MUSE: Over 800 journals and 70,000 books on a single platform.
• THEOLOGICAL BOOK NETWORK: Theological Book Network provides access to free books to most countries outside of the United States, Canada, and the European Union through the International Cooperation Initiative (ICI). The ICI project provides free online PDF files to scholars and students who would not otherwise have access to these resources.