A short but interesting memoir by Julian William Cummings entitled "Grasshopper Pilot" is about flying artillery spotter aircraft in WWII. He flew Piper Cubs, the L-4.
The artillery spotters were assigned to artillery units and some of his interactions with regular Army Air Corps people are enlightening. The combat areas he flew in and described are Africa, Sicily and Italy.
Worth a read.
Made me want to read more about the aircraft, too.
