WHO. (1991). WHO drug information; Vol.5(N.3)/1991. Geneva: WHO.
Chicago Style aipamenaWHO. WHO Drug Information; Vol.5(N.3)/1991. Geneva: WHO, 1991.
MLA aipamenaWHO. WHO Drug Information; Vol.5(N.3)/1991. Geneva: WHO, 1991.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.