Columbia subject headings:
Amusement rides--United States--Safety measures.
Spinal cord--Wounds and injuries--United States.
Tourism--Government policy--United States.
Harvard subject headings:
Amusement rides--United States--Safety measures.
Spinal cord--Wounds and injuries--United States.
Tourism--Government policy--United States
Princeton subject headings:
Amusement rides--United States--Safety measures.
Spinal cord--Wounds and injuries--United States.
Tourism--Government policy--United States.