APA Format
World Health Organization (WHO) . (). Principles of studies on diseases of suspected chemical etiology and their prevention. : Geneva WHO 1987
MLA Format
World Health Organization (WHO) . Principles of studies on diseases of suspected chemical etiology and their prevention. : Geneva WHO 1987,
Australian/Harvard Format
World Health Organization (WHO) . . Principles of studies on diseases of suspected chemical etiology and their prevention. Geneva WHO 1987, 
Warning: These citations may not always be 100% accurate.