Chapter 3. European guidelines for the management of acute nonspecific low back pain in primary care.
van Tulder M, Becker A, Bekkering T, Breen A, del Real MT, Hutchinson A, Koes B, Laerum E, Malmivaara A, COST B13 Working Group on Guidelines for the Management of Acute Low Back Pain in Primary Care. Eur Spine J. 2006 Mar; 15 Suppl 2:S169-91.