Many books and articles were instrumental in helping me to understand the culture and controversies surrounding crop circles. Particularly useful were: Crop Circles: Exploring the Designs and Mysteries by Werner Anderhub and Hans-Peter Roth; “Anatomical anomalies in crop formation plants,” published in Physiologia Plantarium (92) by W.C. Levengood; Secrets in the Fields: The Science and Mysticism of Crop Circles by Freddy Silva; and Crop Circles: The Greatest Mystery of Modern Times by Lucy Pringle. The crop circle illustrations in this book were inspired by the drawings of Leora Franco, featured in Pringle’s book.