1. Boston Public Library, MS pf Med.292 Title: Papal bull in the name of Sixtus IV uniting the church of St. Peter "ad Montonem" with a perpetual chaplaincy dedicated to the Virgin Mary in the church of Atria : in Latin]. Author: Sixtus IV Place: Italy Date: 1474
2. Harry Ransom Center, MS 3327, Container 196 Title: Papal bull Author: Sixtus IV Place: Italy Date: 1474 February 7
3. Western Michigan University, WMU MS 112 Title: Papal bull Author: Sixtus IV Place: Rome Date: 1484.