Call number ranges can be browsed online to include all books in all libraries at Columbia (including offsite). If you are looking at a particular record for a book in CLIO, there is an option to "show" Virtual Shelf Browse directly underneath the information about the book (the default is "hide").
Note that there may be books cataloged under a different call number (such as Z for bibliography) than those listed here.
Holocaust Literature: PN56.H55
Holocaust History: D802-D810