The three most comprehensive citation searching resources are Scopus, Web of Science,and Google Scholar. While the resources are continually expanding their scope, no tool contains all articles and citations and one resource may perform much better for one researcher than another.
Generally, Web of Science and Scopus offer thorough coverage of the sciences. Google Scholar also has good coverage of the sciences, but its tools are less robust and there is little quality control. It's best to try each of these databases and see which one offers you the best results.
The social sciences and arts & humanities have reasonable journal coverage in Web of Science and Scopus, but these database do not cover books. If you are in one of these fields, consider trying JSTOR or EBSCOhost in addition to Google Scholar. You can find instructions for each under the Additional Resources tab.
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|Scopus||Web of Science|
|Total Records||42.5 Million Records (22 million include cited references)||40 million|
|Sources by type||
18,000 peer-reviewed journals
600 Trade publications
350 Book series (mainly science)
3.7 million conference proceedings
|Coverage by date||1996-present for cited references||
Science Citation Index 1965-present
Social Science Citation Index 1956-present
Arts & Humanities Citation Index 1975-present
Conference proceedings 1990-present
|Coverage by subject area||
14,000+ science journals
2,850 journals from the social sciences, arts, and humanities.
6,650 science journals
1,950 social science journals
1,160 arts & humanities journals
Information compiled 1/06/11 from the following sources: