 Their Roman sojourn was decisive for the entire development of Italian art in the 15th century, for it was during this period that Brunelleschi undertook his measurements of the Pantheon dome and of other Roman buildings.Brunelleschi's buildings and Donatello's sculptures are both considered supreme expressions of the spirit of this era in architecture and sculpture, and they exercised a potent influence upon the artists of the age.In Florence, Donatello assisted Lorenzo Ghiberti with the statues of prophets for the north door of the Baptistery of Florence Cathedral, for which he received payment in November 1406 and early 1408.