Mead, Christopher Curtis (1991). Charles Garnier's Paris Opéra: Architectural Empathy and the Renaissance of French Classicism, p. 101. New York: The Architectural History Foundation. Cambridge, Massachusetts: The MIT Press. ISBN 9780262132756. Original: Garnier, Le Nouvel Opéra (1876–1880), folio I, plates 10–11. / Wikimedia Commons

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