www.gogeometry.com

Anchor text: Go Geometry from the Land of the Incas: New domain

Wikipedia: Geometry from the Land of the Incas

Wikipedia: Geometry from the Land of the Incas

Anchor text: Japanese theorem, interactive proof with animation

Wikipedia: Japanese theorem for cyclic quadrilaterals

Anchor text: "Senchin Bajo – Plaza in Peru may be the America's oldest urban site"

Wikipedia: List of oldest extant buildings

Wikipedia: Optic equation

Anchor text: Clawson Point: Orthic Triangle, Extangents Triangle, Homothecy or Homothety

Wikipedia: Clawson point