Where can Melvil Dewey be?

Your friend Melvil Dewey hasn't been at school in a week. Your teacher told you, he moved to Montana, but you cannot believe he didn't tell you! Recently, you received a text message from him. You are determined to figure out where he really is! You head to the library to figure out the mystery but while you're searching for clues you get LOCKED IN! Can you solve all the puzzles, find Melvil and escape from the library? Good luck!