"Defense of Bastogne" by Ralph M. Mitchell (September 1986). Excellent history of the battle, evidently scanned from a published account. See the right-hand bar for 11 detailed maps of the encouter. The writing goes beyond the (undeniable) heroism of the 101st, to a "more detailed look at how the 101st was organized and equipped," and how these factors favored the defense. This analysis begins on page 35. Mitchell's account is supplied by the home page of the 101st Airborne's 1st Brigade "Bastogne Bulldogs."
Online Book: Bastogne: The First Eight Days ("The Story of the First Eight Days In Which the 101st Airborne Division Was Closed Within the Ring of German Forces") by S. L. A. Marshall, with John G. Westover, A. Joseph Webber, Olin Downs (1946), originally from the US Army Center of Military History.
Amazon. Bastogne: Battle of the Bulge by Michael Tolhurst, "Drawing on eyewitness accounts, this excellent book paints a graphic picture of the battle that was at the very center of Hitler's last gamble."
Amazon. Seven Roads to Hell : A Screaming Eagle at Bastogne by Donald R. Burgett. Also in hardcover.
Online Book: "The Battle of Bastogne" chapter from Hugh M. Cole 700-page US Army Center of Military History account, The Ardennes: Battle of the Bulge (1965). The chapter carries the action through Christmas. The relief of Bastogne is covered in the next chapter.
General McAuliffe's "Merry Christmas" letter (December 24, 1944), "NUTS!"