Ceiling with Allegorical Figures and the Arms of Pope Sixtus V (Guerra's outer drawing); Saint Joseph and the Christ Child (Viani's central drawing)
center section (octagon): 23.3 x 16.2 cm (9 3/16 x 6 3/8 in.)  Overall (ceiling design): 51.1 x 41.8 cm (20 1/8 x 16 7/16 in.)  mount: 53.3 x 44 cm (21 x 17 5/16 in.)

About Giovanni Guerra and Domenico Maria Viani