Luo H, Chen M, Yang R, Xu PC, Zhao MH. The association of HLA-DRB1 alleles with antineutrophil cytoplasmic antibody-associated systemic vasculitis in Chinese patients. Hum Immunol. 2011 May;72(5):422–5. doi: 10.1016/j.humimm.2011.02.017. PMID: 21354458.