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Ohlin A, Karlsson M, Düppe H, Hasserius R, Redlund-Johnell I.Ohlin A, et al.Spine (Phila Pa 1976). 1994 Dec 15;19(24):2774-9. doi: 10.1097/00007632-199412150-00007.Spine (Phila Pa 1976). 1994.PMID: 7899978