I was actually able to get some scans made of a couple of the sketches from Comic Con International, San Diego, July 2011, so I thought I would post a more accurate and detailed look at one of the previously posted sketches, Batgirl and Supergirl.
Original Art is drawn on 11 x 16 Canson Pastel Paper with Col Erase Light Blue Pencil, Pitt and Copic Pens, Warm Grey Copic Markers and Prismacolor Pencils.
...^^