Crofton, Patricia M, Catherine Macfarlane, Barbara Wardhaugh, Michael B Ranke, Martin W Elmlinger, Christopher J H Kelnar, and Malcolm F Macnicol. 2005. “Children With Acute Perthes’ Disease Have Asymmetrical Lower Leg Growth and Abnormal Collagen Turnover”. Acta Orthopaedica 76 (6):841-47. https://doi.org/10.1080/17453670510045462.