Probable architect of the circular Romanesque baptistery at Pisa (1152–1265). He also seems to have been responsible for the octagonal Church of San Sepolcro, Pisa (from 1153), and worked at Santa Maria Maggiore, Florence. His likely name was Diotisalvi de Petroni.
W. Papworth (1852);Sturgis et al. (1901–2)