Columbia subject headings:
Environmental policy--European Union countries.
Environmental policy--Turkey.
European Union countries--Foreign relations--Turkey.
Turkey--Foreign relations--European Union countries.
Harvard subject headings:
Environmental policy--European Union countries
Environmental policy--Turkey
European Union countries--Foreign relations--Turkey.
Turkey--Foreign relations--European Union countries
Princeton subject headings:
Environmental policy--European Union countries.
Environmental policy--Turkey.
European Union countries--Foreign relations--Turkey.
Turkey--Foreign relations--European Union countries.