http://www.atlantico.fr/decryptage/pourquoi-casques-velo-ne-protegent-presque-rien-et-aggravent-meme-choses-claude-lievens-souday-1063945.html
https://ecf.com/news-and-events/news/helmet-effectiveness-research-forced-go-back-drawing-board
http://www.cyclehelmets.org/