You can request unavailable items in various ways: Request an unavailable item found in NUsearch from other libraries, or request an item not found in NUsearch, either through WorldCat or directly through the Interlibrary Loan form. ILL items may be picked up from the Library or be requested to be delivered.
The world's most comprehensive catalog of library holdings, particularly (though not exclusively) from North American libraries, containing over 2,000,000,000 records from over 10,000 libraries.