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Letter: Editor's reply to "Editor's pick: The tautological measure of stuff"

Published 4 November 2015

• The candela is fundamentally tied to our ability to perceive light, and is defined with reference to the single frequency at which a standard eye is most sensitive.

Issue no. 3046 published 7 November 2015

Â鶹´«Ã½ issue 3046 cover

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