"Knives of War: An International Guide to Military Knives from World War I to the Present" by Gorden Hughes(Author), Robert A Buerlein(Author) and Barry Jenkins(Illustrator).

If you are interested in tactical knives from an historical aspect then this is the book for you.  The authors have put together a comprehensive history of the tactical knife from WW1 to WW2.

The 11 chapters of this book cover everything from swords,bayonets,knuckle knives,gravity knives, folding knives, ceremonial swords and trench knives. Knives from both sides of WW1 and WW2 are examined here in detail including the famous Fairbairn-Sykes fighting knives. 

The illustrations and photographs are top notch and worth the price of the book by themselves. 

So if you are a military buff who loves combat knives or just a tactical knife enthusiast this book will provide hours of entertainment and insight.