Giorgio Vasari, Lives of the Most Excellent Painters… (1850)
“ Arnolfo, having thus rendered the tower secure by the excellence of his workmanship, it was not difficult for the masters who succeeded him, to erect upon it the lofty campanile that we now see there,—he not having been able to do more in the remaining two years of his life than complete the palace, which has since received, from time to time, those improvements which render it the noble and majestic edifice we now behold. ”
