Columbia subject headings:
Architecture--Competitions--France--Paris.
Architecture--France--Paris--History--21st century--Designs and plans.
Défense (Paris, France)--Buildings, structures, etc.--Competitions.
Paris (France)--Buildings, structures, etc.--Competitions.
Skyscrapers--France--Paris--Designs and plans.
Tall buildings--France--Paris--Designs and plans.
Tour Signal (France, Paris)--Designs and plans.
Harvard subject headings:
Architecture--France--Paris--21st century--Designs and plans.
Architecture--France--Paris--Competitions.
Défense (Paris, France)--Buildings, structures, etc.--Competitions.
Paris (France)--Buildings, structures, etc.--Competitions.
Skyscrapers--France--Paris--Designs and plans.
Tall buildings--France--Paris--Designs and plans.
Tour Signal (France, Paris)--Designs and plans.
Princeton subject headings:
Architecture--France--Paris--21st century--Designs and plans.
Architecture--France--Paris--Competitions.
Défense (Paris, France)--Buildings, structures, etc.--Competitions.
Paris (France)--Buildings, structures, etc.--Competitions.
Skyscrapers--France--Paris--Designs and plans.
Tall buildings--France--Paris--Designs and plans.
Tour Signal (France, Paris)--Designs and plans.