| Britannica's Omega Sources (previously Original Sources) contains more than 350,000 primary source documents and 5,500 complete books in eight major subject areas: World History, U.S. History, Science and Mathematics, Social Science, Literature, Political Science and Law, Language, and Philosophy and Religion. Also includes more than 3,700 illustrations, such as portraits of great thinkers and writers, depictions of events and diagrams in a scientific work. |