References
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Abbate, Carolyn: Unsung Voices. Opera and Musical Narrative in the Nineteenth Century. Princeton University Press. Press. Princeton, NJ, 1991.
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Aeschylus (Anonymous?): Prometheus Bound. Translated by Paul Elmer More and Edited by Whitney J. Oates and Eugene O'Neill Jr. Random House. New York, 1938.
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Borchmeyer, Dieter: Richard Wagner. Theory and Theatre. Clarendon Press. Oxford, 1991.
 
- Cooke, Deryck:
 
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I Saw the World End. Oxford University Press. London. 1979.
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Introduction to the Decca recording of Richard Wagner's 'The Ring of the Nibelung', a spoken commentary on the musical motifs of Wagner's Ring, with musical examples, in three volumes. 1976 (?)
 
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Darcy, Warren: Wagner's 'Das Rheingold.' Clarendon Press. Oxford University Press. Oxford, 1993.
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Donington, Robert: Wagner's 'Ring' and its Symbols. The Music and the Myth. Faber and Faber.London, 1963
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Dunning, Dr. Allen B: A Thematic Guide to the Musical Themes of Richard Wagner's 'Des Ring des Nibelungen' (formerly published on the internet)
 
- Feuerbach, Ludwig:
 
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[TDI] Thoughts on Death and Immortality. Originally published in 1830. Translated by James A. Massey. University of California Press, 1980.
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[EOC] The Essence of Christianity. Originally published in 1841. Translated by George Eliot [the novelist]. Harper Torchbooks. Harper and Row, Publishers. New York, Hagerstown, San Francisco, London, 1957
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[PPF] The Principles of the Philosophy of the Future. Originally published in 1843. Translated by Manfred Vogel. Hackett Publishing Company, 1986.
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[LER] Lectures on the Essence of Religion. Originally published in 1848. Based on a book published in the early 1840's entitled The Essence of Religion, which was intended to fill in some
 


