APA Format
World Health Organization (WHO) . (). Safe use of pesticides, TRS.813. : Geneva WHO 1991
MLA Format
World Health Organization (WHO) . Safe use of pesticides, TRS.813. : Geneva WHO 1991,
Australian/Harvard Format
World Health Organization (WHO) . . Safe use of pesticides, TRS.813. Geneva WHO 1991, 
Warning: These citations may not always be 100% accurate.