Scopus is the largest abstract and citation database of peer-reviewed literature: scientific journals, books and conference proceedings. Delivering a comprehensive overview of the world's research output in the fields of science, technology, medicine, social sciences, and arts and humanities, Scopus features smart tools to track, analyze and visualize research.
The Web of ScienceSM (formerly Web of Knowledge) is today's premier research platform, helping you quickly find, analyze, and share information in the sciences, social sciences, arts, and humanities. You get integrated access to high quality literature through a unified platform that links a wide variety of content with one seamless search
Microsoft Academic Search is an experimental research service developed by Microsoft Research to explore how scholars, scientists, students, and practitioners find academic content, researchers, institutions, and activities. Microsoft Academic Search indexes not only millions of academic publications, it also displays the key relationships between and among subjects, content, and authors, highlighting the critical links that help define scientific research. As is true of many research projects at Microsoft, this service is not intended to be a production Web site, and it will likely be taken offline when appropriate given the research goals of the project.