Paper Folding Geometry . I have an Origami page where I have instructions for making a star from a paper strip knot. I used a link to your page for the proof.
Origami is an ancient Chinese and Japanese art of paper folding.
I gather that Origami gained acceptance in the West in the early 1950s. Very comprehensive bibliographies are available online. A search of the online bookstore has resulted in several dozen books and albums. Unexpectedly, information available online proved to be scarce. Following is my attempt to catch up with the development of the last 50 years of which, regretfully, I knew so little.