OCLC WorldCat database is the OCLC online union catalog. It contains over 43 million records describing library holdings around the world.

Sponsored by the libraries of the Committee on Institutional Cooperation, the University of California, and other partners, HathiTrust is a repository of digitized materials in all disciplines. Its content--primarily scanned books and journals-- may be searched via authors, titles, subjects, and other data elements.

A collection of over 2000 reference resources.

Brief essays by experts on major topics in and assortment of arts and humanities disciplines. Each essay selects and describes the important scholarship on the topic. Items in the annotated bibliographies usually link to library holdings.

The Encyclopaedia of Islam (New Edition) sets out the present state of our knowledge of the Islamic World. It is a unique and invaluable reference tool, an essential key to understanding the world of Islam, and the authoritative source not only on the religion, but also on the believers and the countries in which they live. It embraces articles on distinguished Muslims of every era and origin, on tribes and dynasties, on crafts and sciences, on political and religious institutions, on the geography, ethnography, flora and fauna of the various countries and on the history, topography and monuments of the major towns and cities. In its geographical and historical scope it encompasses the old Arabo-Islamic empire, the Islamic countries of Iran, Central Asia, the Indian sub-continent and Indonesia, as well as the Ottoman Empire and all other Islamic countries. The Encyclopaedia of Islam is the most important reference tool on Islam presently available.