Knots
A tombstone with two trefoil knots in the courtyard of S.Ambrogio church in Milan (what happens if they are closed in a particular way?)
© matematita
The image belongs to the sections...:
Decorations of walls and façades (Anthology of images)
Knots in the city and outside the city (Topology)
S. Ambrogio (From the exhibitions of matematita)
