Who is this legendary coach?

1. He led his team to an undefeated season in 1972, a feat unmatched in modern professional football.
2. Known for his unwavering intensity and demand for perfection, his coaching style was often described as 'tough but fair'.
3. His teams were renowned for their 'No-Name Defense', a unit that consistently shut down high-powered offenses.
4. He authored a book titled 'Don Shula: An American Football Life'.