A mark D4
The coat-of-arms of the town of Pisa, in a man-hole cover, is an example of a rosette with dihedral symmetry of type D4.
© matematita
The image belongs to the sections...:
*4. (D4) (Symmetry)
Coat of arms, trade marks and flags (Anthology of images)
Coat of arms, trade marks and flags (Symmetry)
Drains and manhole covers (Anthology of images)
Drains and manhole covers (Symmetry)
