Wu, C.-H. (2008) “Supplementary pedicle screw fixation in spinal fusion for degenerative spondylolisthesis in patients aged 65 and over: Outcome after a minimum of 2 years follow-up in 82 patients”, Acta Orthopaedica, 79(1), pp. 67–73. doi: 10.1080/17453670710014789.