Scott Graham R, Samsell BJ, Proffer A, Moore MA, Vega RA, Stary JM, Mathern B. Evaluation of glycerol-preserved bone allografts in cervical spine fusion: a prospective, randomized controlled trial. J Neurosurg Spine. 2015 Jan;22(1):1-10. doi: 10.3171/2014.9.SPINE131005
Parsley (Edwards) TL. Review of the phantom respondents: opinion surveys and political representation. J Off Stat. 1994;10(3):351-5.