a few more on-line references, FWTW (and I think the first is best, tho it is NOT the news story I saw recently, which id'ed several commercial providers of anti-plagarism services to the education business.

• UMD
• O'Keefe
• TurnItIn
• One academic view of some key varieties of plagarism
• Chron of Edctn - discussion and
  2001 discussion, also Chron Ed

Much of this lines up nicely with your schema; perhaps some will be useful in terms of additional or alternate views.