CLIPPINGER, David Alva. The Head Voice and Other Problems: Practical Talks on Singing. [s.l.]: Oliver Ditson Company, 1917. S. 24.Je zde použita šablona {{Cite book}} označená jako k „pouze dočasnému použití“.Project Gutenberg etext.
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Nielsen, Rasmus. ‘I ain’t Never Been Charged with Nothing!‘: The Use of Falsetto Speech as a Linguistic Strategy of Indignation. University of Pennsylvania Working Papers in Linguistics. University of Pennsylvania, 2010. Dostupné online [cit. 6 December 2011].Je zde použita šablona {{Cite news}} označená jako k „pouze dočasnému použití“.
