Fritz has been studying the giants for a long time! I've heard L.A. Marzulli say he "stands on the shoulders of Fritz. He has done extensive research and written many books on the subject, and documented over 900 burial mounds in north America! Be sure and check out his books, you will not regret it!http://www.prometheuslenspodcast.com Fritz work:Amazon.com: Fritz Zimmerman: books, biography, latest update