(1919). Safety and Health: The International Safety, Health and Environmental Magazine. Itasca, IL.: National Safety Council, Periodicals Department.
Παραπομπή Chicago StyleSafety and Health: The International Safety, Health and Environmental Magazine. Itasca, IL.: National Safety Council, Periodicals Department, 1919.
Παραπομπή MLASafety and Health: The International Safety, Health and Environmental Magazine. Itasca, IL.: National Safety Council, Periodicals Department, 1919.
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