This guide gives a list of relevant Library of Congress Classification call-number ranges for Russian and Soviet history researchers who like to browse the stacks. Browsers should be aware, however, that, due to space constraints, a substantial proportion of Princeton University Library's collections is stored offsite (catalog records for materials stored offsite include a link for requesting delivery to campus). The collection as a whole can only be surveyed using the books+ feature on the Library's Website or the online catalog. The catalog does not, however, represent all of the material available to Princeton researchers. The Borrow Direct consortial arrangement allows Princeton researchers to access the collections of Brown, Columbia, Cornell, Dartmouth, Harvard, Johns Hopkins, MIT, The University of Chicago, The University of Pennsylvania, and Yale. Materials not available at Princeton University Library but available at the libraries of these other institutions can be requested thorugh the Borrow Direct Service. Materials not available through any of the Borrow Direct partner libraries can be requested through Interlibrary Services.