Columbia subject headings:
Cigarettes.
Drug delivery devices--United States.
Nicotine.
Smokeless tobacco--United States.
Smoking--United States.
Tobacco use--United States.
Harvard subject headings:
Cigarettes
Drug delivery devices--United States.
Nicotine
Nicotine addiction--United States.
Smokeless tobacco--United States.
Smoking--United States
Tobacco use--United States
Princeton subject headings:
Cigarettes.
Drug delivery devices--United States.
Nicotine addiction--United States.
Nicotine.
Smokeless tobacco--United States.
Tobacco use--United States.