Fusion rate and biomechanical stiffness of hydroxylapatite versus autogenous bone grafts for anterior discectomy. An in vivo animal study. - Pintar,F.A.; Maiman,D.J.; Hollowell,J.P.; Yoganandan,N.; Droese,K.W.; Reinartz,J.M.; Cuddy,B. (Spine, 1994)