Verified locator: Primary byline S. G. Parker and B. L. Diffey. British Journal of Dermatology 108(1), 11–16, January 1983; DOI 10.1111/j.1365-2133.1983.tb04573.x. Abstract: thirteen autopsy toenails, fifteen wavelengths over 300–600 nm; irradiation monochromator, integrating sphere and photodiode; correction for nail fluorescence.
Primary Abstract, pubmed.ncbi.nlm.nih.gov/6821639/ : the thirteen measured autopsy toenails exhibited decreasing transmission as wavelength decreased from 600 towards 300 nm. This is a reported spectral trend for the examined material, separate from its detector geometry and fluorescence correction.