Q16 Web of ScienceTM Core Collection[1] (WoS), Google Scholar[2] (GS) and Scopus are citation databases that index all sorts of publications. At the end of 2014, WoS indexed 39 million documents including scientific articles (23 million), papers in proceedings (6 million), meeting abstracts (4 million), book reviews (2 million), and editorials, letters, reviews, and news (4 million). What percentage of the scientific articles (in WoS) have been cited at least once?[3]
more than 90 %
between 80 % and 90 %
between 50 % and 80 %
less than 50 %