ProQuest Dissertations and Theses Global is the world's most comprehensive collection of dissertations and theses, covering materials back to the first U.S. dissertation, accepted in 1861, as well as to European dissertations from the 17th century. The database is the official dissertations repository for the Library of Congress, with 5.5 million bibliographic citations, 3 million full texts, 4,100 contributing institutions worldwide and 250,000 works added annually. Full-text coverage spans from 1743 to the present, with citation coverage dating back to 1637.

Scopus is a large abstract and citation database of peer-reviewed literature, including scientific journals, books and conference proceedings, covering research topics across all scientific and technical disciplines, ranging from medicine and social sciences to arts and humanities. Further, with smart tools totrack, analyze and visualize research, Scopus empowers you to advance your science beyond the text.

The Web of Science™ Core Collection provides researchers with access to the world's leading bibliographic and citation databases. Authoritative, multidisciplinary content covers over 12,000 of the highest impact journals worldwide, including Open Access journals, as well as over 150,000 conference proceedings and more than 50,000 editorially selected books. You'll find current and retrospective coverage in the sciences, social sciences, arts, and humanities, with coverage back to 1900. A unique feature of the WoS is that from any bibliographic record in the database links are available to its cited references, to related articles and to citing articles. In some instances additional links (e.g. to the journal impact factor) may also be available.