Columbia subject headings:
Industrial productivity--Europe--Congresses.
Industries--Europe--Congresses.
Labor productivity--Europe--Congresses.
Harvard subject headings:
Europe--Economic conditions.
Europe--History--Economic aspects.
Industrial productivity--Europe--Congresses.
Industries--Europe--Congresses.
Labor productivity--Europe--Congresses.
Princeton subject headings:
Capital productivity--Europe.
Europe--Economic conditions.
Labor productivity--Europe.