>> In Equation 33, the second line has "…3sigma(1+2AzzPzz/2))pf + …" -- >> should that 2 before Azz be there? I think it's an extra factor that >> doesn't continue with the rest of the derivation. >> >> I'm not sure. > The 2 in front of Azz, in the equation and in the first line of text below the equation, are typos. Oscar