Gjovaag observes that money is present in the earliest Oz books; there are green pennies in use in the Emerald City in The Wonderful Wizard of Oz, and signs of currency, and wealth, and a money economy in the books that follow. The change comes in the fifth book, The Road to Oz (1909), by which time money has disappeared from Oz. The title of Gjovaag's essay is a quote from that book; the Tin Woodman speaks those words in Chapter 15. Gjovaag suggests that Baum's ideas about currency in his utopia were shaped by his own financial difficulties, which forced him to file bankruptcy in 1911. In Baum's later books the economy of Oz seems based on sharing, as though Oz is one large family.
- Eric Gjovaag. "Money in Oz! What a Queer Idea!" The Baum Bugle, Vol. 39 No. 3 (Winter 1995).