English: The interior of Barbier (crater), showing Barbier F, on the far side of the moon. North is down and to the right. This is Figure 238 of Apollo Over the Moon (NASA SP-362, 1978), which has the following caption:

The obvious peculiarity of this crater is its shape, the causes for which are open to speculation. The entire area pictured is in the floor of the 60-km-diameter crater Barbier, located on the lunar far side and centered at 23.9° S, 157.7° E. Barbier is a relatively old crater, and the high density of craters on its floor is evident in this high-resolution photograph from the Apollo 15 panoramic camera. The two angular corners of the oddly shaped crater suggest that its present form is partly controlled by faults or joints in the floor of Barbier. The slightly raised rim of the crater evidenced in the shadow on the rim at the left and the brightening on the rim in the lower right side of the crater-shows that material was ejected from the crater at the time of its formation and that it is not simply a collapsed portion of the floor of Barbier. The long dimension of the pictured crater is 16 km, and the short dimension is 10 km.-M.C.M. (Michael C. McEwen)