SPI 206: How SPI Reader Robert Duff Is Building Passive Income with Books on Amazon

#206: Here with me this week is Robert Duff, Ph.D., a psychologist who's supplementing his income by selling his books on Amazon. We discuss how to create and sell books for print, digital, and audio. Podcast show notes available here: https://www.smartpassiveincome.com/session206 See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.