Source for accessing unclassified reports from U.S. and international government agencies. Provides access to over two million critical citations from government departments such as NASA, the U.S. Department of Energy and the U.S. Department of Defense.
Service of the National Library of Medicine, includes citations for biomedical articles.
Detailed index covering organic and inorganic chemistry. Includes patents. Provides access to chemical reactions and physical, chemical and bioactivity data