See 5031-10:2013-12 for the corrected edition.
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DIN 5031-10
Original price was: $227.00.$113.00Current price is: $113.00.
Optical radiation physics and illuminating engineering – Part 10: Photobiologically effective radiation, quantities, symbols and action spectra
Deutsches Institut Fur Normung E.V. (German National Standard) , 01/01/2013