How do I use call numbers to find a book on the shelf?
A call number is the alphanumeric code that shows you where an item is located on the shelf. It is listed under “Access Options” in HOLLIS. For example: PR9199.4.G867 O63 2022.
At the library, staff and signage will help you match a call number to the correct shelf location.
Harvard’s libraries use over 20 different call numbering systems, also known as classification systems. Library of Congress classification is the most common. Other major systems include Old Widener, Houghton, Tozzer, and Dewey (Schlesinger Library). Call numbers for the same item may differ between libraries.
Not all materials are available to borrow off the shelf. Use the request option presented in HOLLIS if any of the following is true: the item location is “offsite”; the item status is “not in place”; the item displays a “Request to copy or visit” option; there is no call number listed in HOLLIS.
Pro Tip: use the filter “Locations with Browsable Stacks” to limit your results to items in library areas where you can browse the shelves.
Related FAQs
How can I search HOLLIS by call number?
How do I read a Widener call number in order to find something in the stacks?
Why does Widener Library use more than one call number system?
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