Columbia subject headings:
Castles--Conservation and restoration--France--Pierrefonds.
Château de Pierrefonds (Pierrefonds, France)--History.
Facility management--France--Pierrefonds.
Pierrefonds (France)--Buildings, structures, etc.
Viollet-le-Duc, Eugène-Emmanuel, 1814-1879.
Harvard subject headings:
Princeton subject headings:
Architects--France--Correspondence.
Castles--Conservation and restoration--France--Pierrefonds--History--19th century.
Château de Pierrefonds (Pierrefonds, France)--History.
Facility management--France--Pierrefonds--History--19th century.
Pierrefonds (France)--Buildings, structures, etc.
Viollet-le-Duc, Eugène-Emmanuel, 1814-1879--Correspondence.
Viollet-le-Duc, Eugène-Emmanuel, 1814-1879.