Columbia subject headings:
Harvard subject headings:
Carcinogens--Congresses
Drug abuse--United States
HIV (Viruses)--United States.
Kaposi's sarcoma--Congresses.
Nitrites--Toxicology.
Princeton subject headings:
Carcinogens--Congresses.
Drug abuse--United States.
HIV (Viruses)--United States.
Kaposi's sarcoma--Congresses.
Nitrites--Toxicology.