This document provides instructions for finding books in the Brookhaven Elementary Library organized by author's last name. It explains that most fiction books are shelved alphabetically by the author's last name. For the Magic Tree House books by Mary Pope Osborne, students would look in the "Os" section. The call number changes depending on the book section, such as Easy Reader or Chapter books, but the last part stays the same using the first three letters of the author's last name. Within each section, books are arranged alphabetically by author's last name using the spine labels.