Hughes, P. C. (1956). Great opera houses: A traveller's guide to their history and traditions. Weidenfeld and Nicolson.
Chicago-viite (17. p.)Hughes, Patrick Cairns. Great Opera Houses: A Traveller's Guide to Their History and Traditions. London: Weidenfeld and Nicolson, 1956.
MLA-viite (9. p.)Hughes, Patrick Cairns. Great Opera Houses: A Traveller's Guide to Their History and Traditions. Weidenfeld and Nicolson, 1956.
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