Barthel tried to depict 7 lines, while Fischer has attempted to depict 9 lines (of the presumed 12 that originally was there on the only side (a) which has any glyphs left.

The two lines added by Fischer come at the beginning of the text as lines Oa1 and Oa2 in my description.

Therefore the lines of Barthel, a1 - a7,  have been renumbered by me to a3 - a9 (as also Fischer has done).