Premise: Scores of architects worked on the church from the 13th to the 17th centuries (its central bronze doors were added in 1964), but its glory remains the gleaming facade (its mosaics were a 17th-century addition), with its four slender spired pilasters and its rosewindow above the beautifully scrolled porches.

Hypothesis: The church's central bronze doors were added in 1964.
Relation: entailment