There are many books on the last offensive launched by Herr Corporal HITLER.
This attack known as the Battle of the Bulge or the battle at Ardennes was launched on 16 December 1944.
The best book by far on genesis, planning, and the battle is Snow and Steel by Peter Caddick- Adams. Published in 2014, Peter has superb command of his sources. His narrative is brilliant.
At 872-pages, the book is divided into 4 parts. The maps are useful though one should read the hardback for a clearer view. In addition, Peter has given us a useful Glossary, Orders of Battle, notes, and bibliography.