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The word 'aspiration' and the aspiration symbol is sometimes used with voiced stops, such as [dʰ]. However, such "voiced aspiration", also known as breathy voice or murmur, is less ambiguously transcribed with dedicated diacritics, either [d̤] or [dʱ].
Aspiration (phonetics) - Wikipedia, the free encyclopedia
PS: In English we don't do /sb/, /sd/, /sg/
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