Scopus is an interdisciplinary database of abstracts and citations – citation index – of publications in the field of mathematics and natural sciences, technology, medicine and humanities. It is developed by the Elsevier publishing house. It contains about 23,000 peer-reviewed journals (including 3,600 Open Access), 145,000 books, 562 book series, and about 8 million conference reports. More than half of the magazines are from outside the USA. Scopus indexes also scientific websites.