Library books & paper journals are organized by subject and assigned a call number, found on the spine of the book. It usually looks like AA .B01 C02 2015. The first two letters are the subject and the last number will always be the year published.
Math books and journals are found under QA on the basement floor (beige carpet). Some other call numbers of interest start with: BC (Logic), HG (Finance), & TK (Electrical engineering).