2000, Long-term efficacy of radon spa therapy in rheumatoid arthritis – A randomized, sham-controlled study and follow up

Franke A, Reiner L, Pratzel HG, Franke T & Resch KL:

Rheumatology 2000; 39: 894-902. doi: 10.1093/rheumatology/39.8.994.

https://pubmed.ncbi.nlm.nih.gov/10952746/