Vatican: Michelangelo's drawing of St. Peter's Basilica discovered

Vatican - The Vatican annals have released another treasure - a sketch of Saint Peter's Basilica, drawn by the Italian Renaissance genius Michelangelo in the spring of 1563, a few months before his death. This was reported today by the Vatican newspaper l'Osservatore Romano.
According to the paper, this is most likely the very last drawing created by the 88-year-old artist. The small-format drawing depicts part of the dome, including numerical data. It is presumably a guide for stonemasons to know exactly how to work the building material.
The drawing is executed in chalk of a reddish-brown color, which was common among Italian artists of that time. The sheet has likely survived because it was later used for some calculations, probably for craftsmen working on the dome's construction.
The public is to be introduced to this unexpected find next Monday, the paper writes.
Michelangelo worked on the architectural plans for the basilica from 1547 until shortly before his death in 1564.