Ressources Electroniques -> ISI Web of Knowledge

ISI Web of Knowledge provides access to a network of scholarly articles linked by their references. Articles have been indexed from journals since 1960 and 12,000 journals are currently covered. WoS is the online version of the Science Citation Index with some differences. Separate annual editions covering science, social sciences, and the arts and humanities have been integrated into a multiyear multidisciplinary system. WoS covers nearly 23 million source papers from the 1940s to the present, and frequently updated.
Summary: Web of Science is updated with approximately 25,000 articles and 700,000 cited references added each week.
Thomson Reuters Impact Factor
JCR provides quantitative tools for ranking, evaluating, categorizing, and comparing journals. The impact factor is one of these; it is a measure of the frequency with which the « average article » in a journal has been cited in a particular year or period. The annual JCR impact factor is a ratio between citations and recent citable items published. Thus, the impact factor of a journal is calculated by dividing the number of current year citations to the source items published in that journal during the previous two years.