Columbia subject headings:
Communication and traffic--Employees--Labor unions--United States--History.
Communications Workers of America--History.
Telephone companies--Employees--Labor unions--United States--History.
Harvard subject headings:
Communication and traffic--Employees--Labor unions--United States--History.
Communications Workers of America--History.
Telephone companies--Employees--Labor unions--United States--History.
Princeton subject headings:
American Telephone and Telegraph Company--History.
Communication and traffic--Employees--Labor unions--United States--History.
Communications Workers of America--History.
Telephone companies--Employees--Labor unions--United States--History.