Columbia subject headings:
Optometrists--Legal status, laws, etc.--United States.
Optometrists--Malpractice--United States.
Optometry--Practice--United States.
Harvard subject headings:
Optometrists--Legal status, laws, etc.--United States.
Optometrists--Malpractice--United States.
Optometry--Practice--United States.
Princeton subject headings: