Wikipedia
Liouville (crater)
Liouville is a small lunar impact crater that is located near the eastern limb of the Moon. It lies to the southeast of the larger crater Dubyago, and was previously designated Dubyago S before being given a name by the IAU.
The crater is circular and bowl-shaped, with a small interior floor at the midpoint of the sloping interior walls. The western and northwestern rim is attached to a depression in the surface that has the appearance of a distorted crater formation. Farther to the west is the comparably sized Respighi.