Vatican Museums. Photo akg-images/MPortfolio/Electa.

Photo Martin Gayford.

Photo Scala, Florence. Courtesy of the Ministero Beni e Att. Culturali.

Photo Scala, Florence. Courtesy of the Ministero Beni e Att. Culturali.

Photo Scala, Florence/Fondo Edifici di Culto. Min. dell’ Interno.

Photo Scala, Florence/Fondo Edifici di Culto. Min. dell’ Interno.

Photo Scala, Florence.

Photo Scala, Florence.

Photo The Bridgeman Art Library.

The British Museum, London.

Kimbell Art Museum, Fort Worth, Texas.

Photo Scala, Florence.

Photo Scala, Florence.

Photo Scala, Florence.

Photo Cardozo-Kindersley Studio, Cambridge.

Photo Scala, Florence. Courtesy of the Ministero Beni e Att. Culturali.

Photo DeAgostini Picture Library/Scala, Florence.

Photo Scala, Florence.

Photo Scala, Florence.

Photo DeAgostini Picture Library/Scala, Florence.