English:
The best site about green clay, and a forum (maybe not actif anymore)
http://www.eytonsearth.org/
Here are others articles about green clay, not all are good
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2600539/
https://www.medicalnewstoday.com/articles/325241.php
https://link.springer.com/article/10.1007/s10653-016-9903-4
http://lhomme.et.largile.free.fr/presentation/clays_health.htm
https://www.via-les-herbes.com/green-clay-benefits/
commercial site:
http://www.frenchclayforall.com/
French:
http://lhomme.et.largile.free.fr/
https://jade-allegre.com/argiles/liens/?lang=en
https://www.via-les-herbes.com/largile-verte-et-ses-bienfaits/
http://vivreenharmonie.fr/
http://www.wax-argile.be/204783181
http://www.tvplayvideos.com/1/l-argile
http://home.page.ch/pub/sleemy@gkb.com/Argile.html
Nederlands:
http://www.gielenaroma.nl/index.php?page=kompressen---kleipakking
https://dalternative.wordpress.com/2013/09/26/hoe-gebruik-je-groene-klei-oftewel-leem/
http://deelbewust.com/de-kracht-van-groene-leem/
https://www.chi.nl/blog/de-oerkracht-van-klei/
Spanish:
http://lhomme.et.largile.free.fr/presentation/quienes_somos.htm