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.

FRANCIS indexes multilingual information and provides in-depth coverage of humanities and social sciences.

The database OLC Ibero-America, Spain and Portugal is a regional related section from the Online Contents database that is constantly being completed with the addition of selected journals from the competent Libraries, the Library of the Ibero-American Institute Prussian Cultural Heritage (Ibero-America and the Caribbean) and the state and university library SUB Hamburg (Spain and Portugal). Currently more than 1.400 journals are being indexed. Gradually earlier editions of these journals will also be made accessible.