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Koller, Heiko, Axel Hempfing, Luis Ferraris, Oliver Maier, Wolfgang Hitzl, and Peter Metz-Stavenhagen. 4- and 5-level Anterior Fusions of the Cervical Spine: Review of Literature and Clinical Results. Springer-Verlag, 2007.

Koller, Heiko, et al. 4- and 5-level Anterior Fusions of the Cervical Spine: Review of Literature and Clinical Results. Springer-Verlag, 2007.