- Early Christian and Byzantine Art. Baltimore Museum of Art, Baltimore. 1947.
- Treasures in Heaven: Armenian Illuminated Manuscripts. The Morgan Library & Museum, New York; The Walters Art Gallery, Baltimore. 1994.
- Illuminating the Word: Gospel Books in the Middle Ages. The Walters Art Museum, Baltimore. 2004.
- In the Beginning: Bibles Before the Year 1000. Freer Gallery of Art, Washington. 2006-2007.