The best starting point probably is 'A Time For Trumpets' - it's very good. After that, Pallud's massive book, recommended by von Poop above, is well-worth getting hold of ; it contains much from the German point-of-view.

Another big book I'd recommend is the US Official History, 'The Battle Of The Bulge' by Hugh M Cole. This was reprinted in the USA fairly recently and has been available at low cost. Such Official Histories are often very 'dry' but this is an exception ; it's a great read and very detailed.

After that, there are many excellent books containing in-depth stories of individual actions and units - many of these have been discussed elsewhere on the Forum.

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