Columbia subject headings:
Harvard subject headings:
Biomass energy industries--Germany--Rhineland-Palatinate--History.
Biomass energy industries--Luxembourg--History.
Biomass energy--Economic aspects--Germany--Rhineland-Palatinate--History.
Biomass energy--Economic aspects--Luxembourg--History.
Energy development--Germany--Rhineland-Palatinate--History.
Energy development--Luxembourg--History.
Luxembourg--Economic conditions.
Regional planning--Germany--Rhineland-Palatinate--History.
Regional planning--Luxembourg--History.
Rhineland-Palatinate (Germany)--Economic conditions.
Princeton subject headings:
Biomass energy industries--Germany--Rhineland-Palatinate--History.
Biomass energy industries--Luxembourg--History.
Biomass energy--Economic aspects--Germany--Rhineland-Palatinate--History.
Biomass energy--Economic aspects--Luxembourg--History.
Energy development--Germany--Rhineland-Palatinate--History.
Energy development--Luxembourg--History.
Luxembourg--Economic conditions.
Regional planning--Germany--Rhineland-Palatinate--History.
Regional planning--Luxembourg--History.
Rhineland-Palatinate (Germany)--Economic conditions.