Rutten, Matthieu J C M, et al. “Excisional Biopsy of Impalpable Soft Tissue Tumors US-Guided Preoperative Localization in 12 Cases”. Acta Orthopaedica, vol. 68, no. 4, Jan. 1997, pp. 384-6, doi:10.3109/17453679708996182.