In the interior (fourth chapel on left aisle), look for Jacopo della Quercia's marble altar (1422).
Jacopo della Quercia's marble altar was completed in the winter of AD1422.
mnli hypothesis: Jacopo della Quercia's marble altar was completed in the winter of AD1422. premise: In the interior (fourth chapel on left aisle), look for Jacopo della Quercia's marble altar (1422).