1. Low back pain prevention along lumberjacks in Northern Sweden;Åberg,1982
2. Arbetsmiljö och Arbetsorganisation i samband med städning;Ahlstrand;Forskningsrapport Luleå 1980:09,1980
3. Acute low back pain in industry. A controlled prospective study with special reference to therapy and confounding factors;Bergquist-Ullman;Acta Orthopaedica Scandinavica,1977