T. Tsuboyama, R. Windhager, W. Dock, T. Bochdansky, T. Yamamuro, and R. Kotz, “Knee function after operation for malignancy of the distal femur: Quadriceps muscle mass and knee extension strength in 21 patients with hinged endoprostheses”, ActaO, vol. 64, no. 6, pp. 673–677, Jan. 1993.