Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Pretty good as a one book summary of major USMC activity

It seems quite evident that the sources for Murphy's book are unit histories, command chronologies and similar documents. These leave a bit to be desired as they're written by people who toe the party line (so to speak....meaning that the unit commander usually has a say as to what goes in and what gets omitted). As a one volume reference book on where and when the Marines had major engagements however, it is excellent. He is to be commended for including grid coordinates and maps, a great help if you're following along on a tactical map.