APA Format
World Health Organization (WHO) . (). Methods used in establishing permissible levels in occupational exposure to harmful agents. TRS.601. : Geneva WHO 1977
MLA Format
World Health Organization (WHO) . Methods used in establishing permissible levels in occupational exposure to harmful agents. TRS.601. : Geneva WHO 1977,
Australian/Harvard Format
World Health Organization (WHO) . . Methods used in establishing permissible levels in occupational exposure to harmful agents. TRS.601. Geneva WHO 1977, 
Warning: These citations may not always be 100% accurate.