Columbia subject headings:
Construction industry--United States--Personnel management.
Construction workers--Legal status, laws, etc.--United States.
Labor unions--Construction workers--Law and legislation--United States.
Open and closed shop--Law and legislation--United States.
Open and closed shop--United States.
Harvard subject headings:
Construction industry--United States--Personnel management.
Construction workers--Labor unions--Law and legislation--United States.
Construction workers--Legal status, laws, etc.--United States.
Open and closed shop--Law and legislation--United States.
Open and closed shop--United States.
Princeton subject headings:
Construction industry--United States--Personnel management.
Construction workers--Labor unions--Law and legislation--United States.
Construction workers--Legal status, laws, etc.--United States.
Open and closed shop--Law and legislation--United States.
Open and closed shop--United States.