Ademar José Gevaerd (born 1952, also known simply as A. J. Gevaerd) is a Brazilian ufologist, or specialist in the study of Unidentified Flying Objects (UFOs).He is editor of Revista UFO (UFO Magazine), founder and director of the Brazilian Center for Flying Saucer Research (CBPDV) and Brazilian Director for Mutual UFO Network (MUFON). He represents Brazil at the Center for UFO Studies. He has appeared on the Globo Network, the Discovery Channel and the History Channel. He has spoken in many cities in Brazil and in other 29 countries, and has conducted over 700 field investigations of UFO cases in Brazil. He has been described as one of the most respected of ufologists.