เนื้อหาจาก

https://theconversation.com/pi-might-look-random-but-its-full-of-hidden-patterns-55994

http://www.angio.net/pi/

ภาพจาก

http://blog.sarahha.com/tag/pi-jewelry

http://www.clipartpanda.com/categories/hexagon-shape-clip-art

http://etc.usf.edu/clipart/galleries/511-inscribed-shapes