Gaya APA
GOETSCH, D, L., HELBA, S, [. (2002).
Occupational safety and health : .
Upper Saddle River:
Prentice Hall.
Gaya MLA
GOETSCH, David, L.., HELBA, Stephen, [ed.].
"Occupational safety and health :".
Upper Saddle River:
Prentice Hall,
2002.
Buku.