1. IES Lighting Handbook, 5th Edition, Illuminating Engineering Society, 345 East 47th Street, New York, N. Y. 10017, 1972, p. 25–15 and 25–16 (Fig. 25–23).
2. Committee on Nomenclature of the IES, American national standard nomenclature and definitions for illuminating engineering, Illuminating Engineering Society (Sponsor), 345 East 47th Street, New York, N. Y. 10017, p. 37, Table 13.8.
3. A New Standard of Spectral Irradiance
4. A Computer Based Spectroradiometer System