APA
WHO, . (1987). Principles of studies on diseases of suspected chemical etiology and their prevention. Web result with site links: WHO Regional Publications.
Chicago
WHO, . 1987. Principles of studies on diseases of suspected chemical etiology and their prevention. Web result with site links: WHO Regional Publications.
Harvard
WHO, . (1987). Principles of studies on diseases of suspected chemical etiology and their prevention. Web result with site links: WHO Regional Publications.
MLA
WHO, . Principles of studies on diseases of suspected chemical etiology and their prevention. Web result with site links: WHO Regional Publications. 1987.