Many scholars affirm Semitic quality of the Synoptic Gospel material as indicative of earlier material, but how to determine Semitic quality has been hotly debated. Recently this subject of a Hebrew Gospel and Semitic material has been discussed by James R. Edwards (although with somewhat differing results than Jerusalem School members). The most extensive Jerusalem School publication on Semitic material and types of Semitic interference can be found in an extended essay and appendix (critical notes) in Jesus' Last Week (Leiden: Brill, 2006).