Thanks for the recommendation, Rick!
Of course, I would also recommend that you should go directly to the primary source,
Jagd in Flanderns Himmel by Bodenschatz, and/or the superb translation by Jan Hayzlett,
Hunting with Richthofen; the Bodenschatz Diaries.
By all means seek out Peter Kilduff's awesome
The Red Baron Combat Wing, (Arms & Armour, 1997), a wonderfully researched and footnoted history of JG I.
The Grub Street series is vital, especially
The Jasta War Chronology by Duiven, Franks and Bailey.