APA Format
World Health Organization (WHO) . (). Hydrogen sulfide: humab health aspects, CICAD.53. : Geneva WHO 2003
MLA Format
World Health Organization (WHO) . Hydrogen sulfide: humab health aspects, CICAD.53. : Geneva WHO 2003,
Australian/Harvard Format
World Health Organization (WHO) . . Hydrogen sulfide: humab health aspects, CICAD.53. Geneva WHO 2003, 
Warning: These citations may not always be 100% accurate.