Work environment and neck and shoulder pain: the influence of exposure time. Results from a population based case-control study
K Fredriksson, L Alfredsson, G Ahlberg, M Josephson, A Kilbom, H Wigaeus, C Wiktorin, and E Vingard
Occup Environ Med. 2002 March; 59(3): 182–188. doi: 10.1136/oem.59.3.182.PMCID: PMC1763625