Heldt C, Listing J, Sözeri O, Bläsing F, Frischbutter S, Müller B. Differential expression of HLA class II genes associated with disease susceptibility and progression in rheumatoid arthritis. Arthritis Rheum. 2003 Oct;48(10):2779–87. doi: 10.1002/art.11251. PMID: 14558083.