When Mrs Livingston shows Eddie his father's important-document lock box, several books are seen on the desk in Tom's bedroom, including: "The Odyssey of an Optimist", by Meyer W. Weisgal (New York: Atheneum, 1967); "A Shop in the High Street", by Sybil Leek (New York: David McKay, 1964); "Pocketful of Raisins", by Margaret Crary (New York: David McKay, 1964); and "Magic in Your Pockets", by Bill Severn (New York: David McKay, 1964, and Young Readers Press, 1967).