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This is a revised, abridged version of Nassour's 1981 biography, and still stands as the most authoritative Cline bio available. It is also highly personal and emotional in its approach: this is a person who clearly loved Patsy Cline.
A good book for the serious fan, although it may be harder to get through for the casual listener. It includes interviews with June Carter, Tompall Glaser, Wanda Jackson, Faron Youngin, and a foreword by Loretta Lynn.