The Verge

Pi Day is here and Google’s calculator will test how well you know the mathematical constant

It’s Pi Day, the nerdiest of holidays because it’s all about a mathematical constant that represents the ratio of a circle’s circumference to its diameter (yes ...
Nature

A Triangle that gives the Area and Circumference of any Circle, and the Diameter of a ...

MATHEWS, G. A Triangle that gives the Area and Circumference of any Circle, and the Diameter of a Circle equal in Area to any given Square. Nature 93, 110 (1914 ...