Akal, Masami, Akio Tateishi, Rikuo Machinami, Kunio Iwano, and Takeshi Asao. “Chondroblastoma of the Sacrum: A Case Report”. Acta Orthopaedica 57, no. 4 (January 1, 1986): 378–381. Accessed May 4, 2026. https://actaorthop.org/actao/article/view/23132.