Hank Harrison (1941- ) is an American writer and publisher and sometimes better known as the father of the singer, Courtney Love and father-in-law of the late Kurt Cobain. Among a range of subjects he has expressed great interest in Megalithic Europe in two of his books, The Stones of Ancient Ireland(a) and Finding Atlantis. In the latter, he supports the idea of a megalithic Atlantis with its centre of power probably located in the Morbihan area of Brittany.
Another recent book by Harrison is Arthur the God(b).
(a) https://www.arkives.com/soai/soai.pdf (offline Mar.2016) see Archive 2930)