^Oscar Thompson; Nicolas Slonimsky (1956). The International Cyclopedia of Music and Musicians. Dodd, Mead. p. 2389.
^Thornton, Ian W. B. (1997). Krakatau: the destruction and reassembly of an island ecosystem (reprint, illustrated ed.). Harvard University Press. p. 307. ISBN 978-0-674-50572-8. Retrieved 27 October 2010.
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