1. Design principles, biomechanical data and clinical experience with a polycentric knee offering controlled stance phase knee flexion: A preliminary report;Blumentritt;Journal of Prosthetics and Orthotics,1997
2. Beyond the four-bar knee;Breakey;Journal of Prosthetics and Orthotics,1998
3. The influence of four-bar linkage knees on prosthetic swing-phase floor clearance;Gard;Journal of Prosthetics and Orthotics,1996
4. Four bar linkage knee analysis;Greene;Orthot Prosthet,1983
5. Modern prosthetic knee mechanisms;Michael;Clin Orthop Rel Research,1999