The University Libraries hours for the holidays are:

December 18-19 (Sat-Sun): CLOSED
December 20 (Mon): 8:00 am - 7:30 pm
December 21-22 (Tues-Wed): 8:00 am - 5:00 pm
December 23-27 (Thurs-Mon): CLOSED

December 28-29 (Tues-Wed): CLOSED due to inclement weather
December 30-January 2 (Thurs-Sun): CLOSED

January 3-7 (Mon-Fri): 8:00 am - 6:00 pm(Diehn Composers Room and Art Library close at 5:00pm)
Regular hours resume January 8.

See Hours & Information on the library web site.