Andrew J. Birtle. "PROVN, Westmoreland, and the Historians: A Reappraisal." The Journal of Military History 72.4 (2008): 1213-1247.

might be of use.

It probably should be read in the context of Lewis Sorley's "A Better War," since IIRC it tends to quarrel with some its (Sorley's) claims.

OC