5Monteiro M, Cunha T, Catarino A, et al. Sacrococcygeal teratoma with malignant transformation in an adult female: CT and MRI findings. Br J Radiol, 2002,75:620-623.
6Samartzis D, Marco RA. Osteochondroma of the sacrum: a case report and review of the literature. Spine,2006,31 :E425-429.