Representative res estimate for no-PDF (yellow) study; author preference unknowable. Value -0.5975 confirmed against Dahl DEDD ref F&K62 (El-r IR -0.5975); Dahl cross-check CONFIRMED.
Fisher, F.M., and G.S. Kaysen (1962): “A Study in Econometrics: The demand for electricity in the United States.” North-Holland Pub. Co.: Amsterdam