CliffsNotes for history?

I seriously doubt that a decent historical treatise can be written in only 50 pages. These sound like they were designed to help a student cram for an exam. The one thing I don't like is that they do not list the author on Amazon's page. I never buy a history of anything unless I can check the author's credentials.
ETA: I just downloaded one on Thomas Jefferson. The book itself never lists the actual author, it only says the author is "Hourly History." So absolutely no way to verify who the author is or what her/his credentials are.