http://www.cracked.com/article_16871_6-insane-discoveries-that-science-cant-explain.html
http://www.ancient-origins.net/artifacts-ancient-technology/6-advanced-ancient-inventions-beyond-modern-understanding-002652
http://www.ranker.com/list/mysterious-ancient-scientific-discoveries-and-inventions/kellen-perry
http://unexplained.co/news/6-advanced-ancient-inventions-which-modern-science-cannot-explain/5539/
http://mentalfloss.com/article/81445/15-intriguing-facts-about-antikythera-mechanism
https://en.wikipedia.org/wiki/Stone_spheres_of_Costa_Rica
https://en.wikipedia.org/wiki/Mithridates_VI_of_Pontus
https://en.wikipedia.org/wiki/Flexible_glass
http://www.theepochtimes.com/n3/1149292-6-advanced-ancient-inventions-beyond-modern-understanding/
http://www.rense.com/general29/chin.htm
http://www.amusingplanet.com/2014/02/the-walls-of-sacsayhuaman.html
https://en.wikipedia.org/wiki/Great_Pyramid_of_Giza