 He has also written a book on antiquities trade with Fredrik Norland Hagen.Ryholt's study makes note of numerous recent archaeological finds including the discovery of a new Hyksos king named Sakir-Har, the find of a doorjamb at Gebel Antef in the mid-1990s which establishes that Sekhemre Shedtawy Sobekemsaf (Sobekemsaf II here) was the father of the 17th Dynasty Theban kings Antef VI and Antef VII.He also discusses Ahmose's Unwetterstele document.