The Ryan book is rather dated now, but Beevor's book is good, as are all of his.
The book above takes advantage of more material that has been made available in recent years; another very good book on the subject is 'The Devils Birthday' by Geoffrey Powell, and another obvious one is 'A Drop Too Many' by Maj, Gen.John Frost.
For me, the big unsung hero of the battle was Stanislaw Sosabowski, commander of the Polish Brigade, he seems to have been one of the few people who really understood what was going on and what needed to be done. Its a great shame that his part, and that of his men was unjustly played down by the British Command, and he was even made a scapegoat.
“O Lord God, let me not be disgraced in my old days.”
'We few, we happy few, we band of brothers'