Columbia subject headings:
Harvard subject headings:
Herbicides--Environmental aspects
Herbicides--Environmental aspects--Vietnam.
Herbicides--Toxicology
Herbicides--Toxicology--Vietnam.
Herbicides--Vietnam--War use.
Herbicides--War use
Herbicides--War use--Vietnam.
Princeton subject headings:
Herbicides--Environmental aspects--Vietnam.
Herbicides--Environmental aspects.
Herbicides--Toxicology--Vietnam.
Herbicides--Toxicology.
Herbicides--Vietnam--War use.
Herbicides--War use.