What source or reference book does Georgie use in her attempt to find her sister in the novel, One Came Home?

The Prairie Traveller: A Hand-Book for Overland Expeditions is a survival manual by U.S. Army Captain Randolph B. Marcy that is kept in Georgie’s house. She consults and brings the book along on her adventure to find her sister, gleaning important and useful information from it, such as what to pack for the trip, and how.