Colom-Beauchamp, Eduardo, et al. “The Use of Bone Morphogenetic Protein in Spinal Transforaminal Lumbar Interbody Fusion: Our Experience”. Puerto Rico Health Sciences Journal, vol. 36, no. 3, Sept. 2017, pp. 173-8, https://prhsj.rcm.upr.edu/index.php/prhsj/article/view/1469.