"TT320 a Re-examination by Prof. Dr. Erhart Graefe. In 1891 one of the saddest events in Egyptology happened when the cache tomb of TT320 was cleared in 48 hours. No photos were taken, no notes and as a consequence much knowledge has been lost. The purpose of the German/Russian Mission was to try and get a clearer plan of the tomb."
See Jane Akshar's Luxor News Blog for the full account.