https://ar5iv.labs.arxiv.org/html/1205.2871
[1205.2871] Mixing of blackbodies: entropy production and dissipation of sound waves in the early...
Mixing of blackbodies with different temperatures creates a spectral distortion which, at lowest order, is a -type distortion, indistinguishable from the...
https://www.nist.gov/publications/spectral-radiance-comparisons-two-high-temperature-blackbodies-temperatures-determined
Spectral Radiance Comparisons of Two High-Temperature Blackbodies With Temperatures Determined...
high temperaturespectralradiancecomparisonstwo