Model from [George Bain’s reference book](http://www.worldcat.org/oclc/41153804), p. [51](https://books.google.fr/books?id=tSRgDwAAQBAJ&pg=PA51) plate 13, credited as originally from the [Book of Kells](https://digitalcollections.tcd.ie/collections/ks65hc20t) (full circular figure extrapolated from a semi-circular "lunette" at the bottom center of [folio 32v](https://digitalcollections.tcd.ie/concern/parent/hm50tr726/folios/n296wz391)). Redrawn in Adobe Illustrator in 2008, converted to 3d curve in Blender in 2009.
Some modern reuse examples:
[](https://www.zazzle.com/z/tchcp0jc) [](https://www.pewtergiftware.com/never-ending-knot-pocket-watch-180-p.asp)
[](https://www.canalbd.net/traitsdesprits_catalogue_detail_--9782302052260)