Text: Brunelleschi is at his most elegant in the Old Sacristy at the end of the left transept (site of a few Medici tombs), decorated with four Donatello wall-medallions (the artist himself is buried in the left transept).
Entailment: The Old Sacristy, where some Medici tombs are found, is adorned by the art of Donatello.
Contradiction: Donatello alone designed the entirety of the Old Sacristy.