2007, Effects of mud-bath treatment on fibromyalgia patients: a randomized clinical trial.

Fioravanti A, Perpignano G, Tirri G, Cardinale G, Gianniti C, Lanza CE, Loi A, Tirri E, Sfriso P, Cozzi F
Rheumatol Int. 2007 Oct;27(12):1157-61. Epub 2007 May 23

https://www.ncbi.nlm.nih.gov/pubmed/17520260?dopt=Abstract