Grondal, Lollo, Birgitta Tengstrand, Birgitta Nordmark, Per Wretenberg, and André Stark. 2008. “The Foot: Still the Most Important Reason for Walking Incapacity in Rheumatoid Arthritis: Distribution of Symptomatic Joints in 1,000 RA Patients”. Acta Orthopaedica 79 (2):257-61. https://doi.org/10.1080/17453670710015067.