http://en.wikipedia.org/wiki/Miami_Circle, http://www.atlasobscura.com/places/miami-circle
http://miami.cbslocal.com/2011/02/23/piece-of-ancient-history-opens-to-public-in-modern-miami,
http://www.labyrinthina.com/circle.htm, http://www.earthmatrix.com/miamicircle, http://www.stonepages.com/news/archives/002662.html,
http://www.weirdus.com/states/florida/ancient_mysteries/miami_mystery_circle/index.php
