Columbia subject headings:
Child labor--United States.
Employers' liability--Indiana.
Employers' liability--United States.
Employers' liability--Wisconsin.
Workers' compensation--United States.
Harvard subject headings:
Child labor--Indiana.
Child labor--United States
Child labor--Wisconsin.
Employers' liability--Indiana.
Employers' liability--United States.
Employers' liability--Wisconsin.
Workers' compensation--Indiana.
Workers' compensation--United States.
Workers' compensation--Wisconsin.
Princeton subject headings: