https://www.aerobuzz.fr/industrie/la-faa-definit-les-regles-de-certification-pour-lextremite-daile-mobile-du-777x/
https://www.flightglobal.com/news/articles/faa-sets-certification-rules-for-777x-wingtip-448708/
https://aviation.stackexchange.com/questions/19289/why-has-the-folding-wing-option-of-the-boeing-777-never-been-ordered
