Textbooks can be ordered through the University of Northern Colorado Bookstore & Fan Shop. Click on Textbooks in the top menu to select a course and find the required books for it.
Your professors may put the books on reserve at the library, but this is not always the case. Check the Reserves tab on the library homepage for each course.
UNC libraries may have the textbook you need in its regular collection, though only a few textbooks are purchased. On the homepage, enter the title or author in the Catalog tab search box to find out.
