Hayes Stephen K. Ninja. Volume IV: Legacy of the Night Warrior

Ohara Publications, 1985. — 191 p.Heading further down the warrior’s path while delving into both the ancient and modern history of ninjutsu, the topics include combat training drills, the emergence and techniques of female ninja agents, exercises to increase awareness, and the goton-po theory of escape and invisibility. The concise writing and numerous photographs make the subject matter clear to the experienced martial artist and the novice.