Kilder:
1. "Ankyloserende spondylitis", på MedicineNet.com - https://www.medicinenet.com/ankylosing_spondylitis/article.. htm
2. "Ankyloserende spondylitis", på eMedicine ved Wilfred CG Peh, MD, MBBS, FRCP (Glasg), FRCP (Edin), FRCR, MSHM, klinisk professor, Faculty of Medicine, National University of Singapore, seniorkonsulent radiolog, Programme Office, Singapore Health Services - https://www.emedicine.com/RADIO/topic41.
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