O'Donoghue, N. D. (2001). The angels keep their ancient places: Reflections on Celtic spirituality. T&T Clark.
Chicago-viite (17. p.)O'Donoghue, Noel Dermot. The Angels Keep Their Ancient Places: Reflections on Celtic Spirituality. Edinburgh: T&T Clark, 2001.
MLA-viite (9. p.)O'Donoghue, Noel Dermot. The Angels Keep Their Ancient Places: Reflections on Celtic Spirituality. T&T Clark, 2001.
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