Looking for a book on SHAEF's organisation (Supreme Headquarters Allied Expeditionary Force), I have read part of David Jablonsky's book.
David Jablonsky is a retired US Army Infantry colonel. Graduated of the US Army Command, Staff College and US Army War College, he also has been professor at the US Army War College where he held different Chairs, on strategy and military studies.
The book is very well documented, ending with 50 pages of notes quoting the references Jablonsky has used.
It is divided in 6 parts :
1. Formative years (1903-1941)
2. Wartime Unified Command (41-42)
3. Wartime Unity of Command and Effort (42-45)
4. Peacetime Unification ((45-50)
5. Peacetime Unity of Effort and Command (50-52)
6. Peacetime Unification and Unity of Effort and Command (52-58).
I have been impressed by the precision and insight view of Eisenhower's thinking towards unified command. The book is detailed, helping us to understand a little more on Eisenhower's experience and path from his education to post-WWII. However, you'll need some knowledge on WWII, and it's hotspots, to fully benefit from this reading.
Personally, I found it interesting to know better on Eisenhower's experience and how he has been convinced of the importance of Unified Command for the success of operations. Some pieces of information on how characters as Eisenhower and Montgomery managed this period, despite differences of appreciation, is also relevant to better understand WWII command and decisions.