Não informado. (1953). Occupational health bulletin. Department of National Health and Welfare, Industrial Health Division.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Occupational Health Bulletin. Ottawa: Department of National Health and Welfare, Industrial Health Division, 1953.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Occupational Health Bulletin. Department of National Health and Welfare, Industrial Health Division, 1953.
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