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I am unable to find anything in the literature to back up the claim that appears all over the internet that:

The modern candlepower now equates directly to the number of candelas.

Can anyone please suggest something in the scientific literature to back up this statement?

If this is not the correct stack exchange for this question, please suggest a better one.

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up vote 6 down vote accepted

Perhaps this paper is what you are looking for?

A quote:

The form of primary standard of light (Fig. 1) now in force internationally consists of a black-body (or cavity) radiator held at the temperature of freezing platinum (2042° K). The corresponding unit of luminous intensity is the 'can- dela' (cd). By definition, the brightness or luminance of the radiator is 60cd/cm2. The figure 60 was chosen to ensure con- tinuity, so that, within limits of experimental error at the various relevant dates, an intensity of 1 cd is the same as the older international candle, which in turn was approximately equal to the intensity of the earliest standard sperm candle.

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This definition was valid from 1948 to 1979. The new definition is 1 cd = 1/683 W/sr of monochromatic light at 540 THz. – Edgar Bonet Jan 11 '12 at 12:53
hehehehe, freezing platinum – Emilio Pisanty Aug 1 '12 at 23:00

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