A reduced-coordinate presentation is devised for the emission of thermal radiation by solid materials. When experimental data are plotted on the reduced coordinates, a temperature-independent curve is obtained and the data for each substance needs only a single parameter for full description. These results may be used to predict emittance of sufficient accuracy for estimation purposes with a minimum number of experimental observations.
RICHARD B. ZIPIN, "Reduced-Coordinate Presentation of the Emission of Thermal Radiation by Solids," J. Opt. Soc. Am. 56, 1543-1545 (1966)