HAMMER, W. (1989). Occupational safety management and engineering (Ed.4.). Prentice Hall.
Chicago-viite (17. p.)HAMMER, Willie. Occupational Safety Management and Engineering. Ed.4. New Jersey: Prentice Hall, 1989.
MLA-viite (9. p.)HAMMER, Willie. Occupational Safety Management and Engineering. Ed.4. Prentice Hall, 1989.
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