GDG- Books about sharpshooter units

[Tom Ryan]

Just got hold of a copy of Fred L. Ray's "Shock Troops of the Confederacy:
The Sharpshooter Battalions of the Army of Northern Virginia."  Has anybody
read it, and what do you think?  It looks like a terrific in-depth study
from all outward appearances.

Is there anything equivalent to this book that deals with all of the Army of
the Potomac sharpshooter units other than those that focus just on Berdan's?

Tom Ryan