1. Once is Enough” in Radiometric Calibrations;Fraser;Journal of Research of the National Institute of Standards and Technology,2007
2. NIST MEASUREMENT SERVICES: Spectral Irradiance Calibrations;Yoon;National Institute of Standards and Technology Special,2011
3. “1.13: Lambertian Surface.” https://phys.libretexts.org/Bookshelves/Astronomy_Cosmology/Book (2017).