1. The Frequency of Occurrence, Impact, and Cost of Selected Musculoskeletal Conditions in the United States;Holbrook,1984
2. Low back pain in industry;Snook,1982
3. Low back trouble in a general population of 30-, 40-, 50-, and 60-year old men and women: study design, representativeness and basic results;Biering-Sørensen;Dan Med Bull,1982
4. A prospective study of low back pain in a general population. I. Occurrence, recurrence and aetiology;Biering-Sørensen;Scand J Rehabil Med,1983
5. Descriptive epidemiology and public health aspects of low back pain;Heliovaara;Ann Med,1989