Demigods and Magicians : Three Stories from the World of Percy Jackson and the Kane Chronicles – Rick Riordan
For Magnus Chase: Hotel Valhalla Guide to the Norse Worlds (an Official Rick Riordan Companion Book) : Your Introduction to Deities, Mythical Beings, & Fantastic Creatures – Rick Riordan
From Percy Jackson: Camp Half-Blood Confidential : Your Real Guide to the Demigod Training Camp – Rick Riordan
