Overgaard, Søren, et al. “The Uncemented Bipolar Hemiarthroplasty for Displaced Femoral Neck Fractures: 6-Year Follow-up of 171 Cases”. Acta Orthopaedica, vol. 62, no. 2, Jan. 1991, pp. 115-20, doi:10.3109/17453679108999236.