Science Citation Index
The Science Citation Index (SCI) is a citation index originally produced by the Institute for Scientific Information (ISI) and created by Eugene Garfield in 1960, which is now owned by Thomson Reuters.  The larger version (Science Citation Index Expanded) covers more than 6,500 notable and significant journals, across 150 disciplines, from 1900 to the present. These are alternately described as the world's leading journals of science and technology, because of a rigorous selection process.
The index is made available online through the Web of Science database, a part of the Web of Knowledge collection of databases. (There are also CD and printed editions, covering a smaller number of journals). This database allows a researcher to identify which later articles have cited any particular earlier article, or cited the articles of any particular author, or determine which articles have been cited most frequently. Thomson Reuters also markets several subsets of this database, termed "Specialty Citation Indexes", such as the Neuroscience Citation Index and the Chemistry Citation Index.
- Arts and Humanities Citation Index, which covers 1130 journals, beginning with 1975.
- Impact factor
- List of academic databases and search engines
- Social Sciences Citation Index, which covers 1700 journals, beginning with 1956.
- Garfield, Eugene (1963). "Science Citation Index" (Free PDF download). Science Citation Index 1961. Garfield Library - UPenn. Retrieved 2013-05-27.
- Originally published by the Institute of Scientific Information in 1963
- Other titles in this document are: What is a Citation Index? , How is the Citation Index Prepared? , How is the Citation Index Used? , Applications of the Science Citation Index , Source Coverage and Statistics , and a Glossary.
- The evolution of the Science Citation Index (Free PDF download). doi:10.2436/20.1501.01.10. International Microbiology (2007) Vol. 10 pp. 65-69
- "History of Citation Indexing" (Free HTML download). Needs of researchers create demand for citation indexing. Thomson Ruters. November 2010. Retrieved 2010-11-04.
- "Science Citation Index Expanded". Retrieved 2009-08-30.
- "Science Citation Index". Retrieved 2009-08-30.
- Jiupeng Ma, Hui-Zhen Fu, and Yuh-Shan Ho Ma, Jiupeng; Fu, Hui-Zhen; Ho, Yuh-Shan (December 2012). "The Top-cited Wetland Articles in Science Citation Index Expanded: characteristics and hotspots". Environmental Earth Sciences. doi:10.1007/s12665-012-2193-y. (Springer-Verlag)
- Ho, Yuh-Shan (2012). "The top-cited research works in the Science Citation Index Expanded". Scientometrics 94 (3): 1297. doi:10.1007/s11192-012-0837-z.
- "Specialty Citation Indexes". Retrieved 2009-08-30.
- "Journal Search - Science -". Retrieved 2009-08-30.
- "Journal Search - Science - Thomson Reuters". Retrieved 14 January 2011.