Fels, S. B., 1979: Simple strategies for inclusion of Voigt effects in infrared cooling rate calculations. Applied Optics, 18 (15), 2634-2637.

Abstract: A line shape with rectangular core and v^-2 wings is shown to be an excellent alias for the Voigt profile when calculating equivalent widths. It leads to closed analytic forms in the commonly employed random models and gives highly accurate ozone cooling rates. An even simpler device for applications where less accurate results are required involves use of the Lorentz profile with a width which does not vanish at zero pressure.