Columbia subject headings:
Architecture.
Viollet-le-Duc, Eugène-Emmanuel, 1814-1879--Criticism and interpretation.
Harvard subject headings:
Architecture, Modern--19th century--France.
Architecture--Conservation and restoration--France.
Architecture--France--Conservation and restoration.
Architecture--France--History--19th century
Viollet-le-Duc, Eugène-Emmanuel, 1814-1879--Criticism and interpretation.
Princeton subject headings:
Architecture--Conservation and restoration.
Architecture--France--Conservation and restoration.
Viollet-le-Duc, Eugène-Emmanuel, 1814-1879--Criticism and interpretation.