Holen, Ketil J, Agnar Tegnander, Terje Terjesen, Ole J Johansen, and Sturla H Eik-Nes. “Ultrasonography of Clinically Unstable Hips: A Prospective Study of 143 Neonates at Birth and Early Follow-up”. Acta Orthopaedica 68, no. 6 (January 1, 1997): 527–532. Accessed April 29, 2026. https://actaorthop.org/actao/article/view/20796.