Are we all agreed the answer is e? (pi wasn’t an option.)
Alright. And ordered some books too.
Robert Harbin - author page on Amazon
Robert J. Lang - author page on Amazon
Such - RL is the NASA engineer in one of the previous videos and not only has he developed relevant folding designs for space craft materiel, he left NASA in the early 2000s to see if he could make a living doing origami. Wonderful entrepreneurial streak there.
And here from my art supply box - origami paper from Kyoto circa 1997.
Probably all of us know how to make cranes and small inflatable boxes, but there is so much more...!