2.43 Campbell (1984) & K.W. Campbell (1988) reported in Joyner and Boore (1988)

8Thenhaus et al. (1989) summarise a model by K.W. Campbell (1984, 1987) where: a = -3.303, b = 0.85, d = -1.25, h1 = 0.0872, h2 = 0.678, e1 = 0.34 and includes an anelastic term -0.0059r (σ is not reported), which they use for western Saudi Arabia.