Scopus is a large abstract and citation database of research literature and patents. The database is updated daily and contains over 70 million records. Scopus indexes nearly 22,000 peer-reviewed journals from more than 5,000 publishers, including 4,200 open access journals. Scopus also indexes 280 trade publications, over 100,000 conferences, over 8 million conference papers, and 560 book series. Additionally, the database contains 39 million patent records from five patent offices.