Eugène Viollet-le-Duc (1814–1879) was a French architect and author, famous for his restoration of the most prominent medieval landmarks in France and elsewhere. His restoration projects included Notre-Dame de Paris, the Basilica of Saint-Denis, and the Sainte-Chapelle, where he also designed new stained-glass windows. His final major restoration project was the Lausanne Cathedral.
Viollet le Duc wrote over 100 publications on architecture, decoration, history, archeology etc., among them the Dictionnaire raisonné de l'architecture française du XIe au XVIe siècle, 1854–1868. A large article in volume IX (1868) is dedicated to stained glass and its restoration. Viollet-le-Duc had many disciples and wrote prefaces for other publications, such as Les arts arabes (1873) by Jules Bourgoin and Architecture et décoration turque au XVe siècle(1874) by Léon Parvillée.

Johnson, J. R. (1963). The Stained Glass Theories of Viollet-Le-Duc. The Art Bulletin, 45(2), 121–134. https://doi.org/10.2307/3048077

Jordan, A. A. (1998). Rationalizing the Narrative: Theory and Practice in the Nineteenth-Century Restoration of the Windows of the Sainte-Chapelle. Gesta, 37(2), 192–200. https://doi.org/10.2307/767259

Pillet, E. (2010). Le vitrail à Paris au XIXe siècle. Entretenir, conserver, restaurer. Rennes.