Columbia subject headings:
Ballot--Security measures--United States.
Ballot--United States.
Elections--Corrupt practices--United States--Prevention.
Voting--United States.
Harvard subject headings:
Ballot--United States.
Security systems--United States.
Voting--United States
Princeton subject headings:
Ballot--Security measures--United States.
Ballot--United States.
Elections--Corrupt practices--United States--Prevention.
Voting--United States.