Columbia subject headings:
Harvard subject headings:
Chatzopoulos, Kōstantinos, 1868-1920--Contributions in Greek labor movement.
Greece--Economic conditions.
Labor movement--Greece--History.
Socialism
Princeton subject headings:
Chatzopoulos, Kōstantinos, 1868-1920.
Greece--Economic conditions--1863-1918.
Labor movement--Greece--History.
Socialism.