ln(h/ho) = a1 ×X1/3 + a2 ×X4/3 + ln(a5) , where X = (a3 - T) / (T - a4) and ho = 1 Pa×s
ln(h/ho) = A + B/T + C/T2 + D/T 3
lg(h/ho) = A + B/T + C×T + D×T 2
ln(h/ho) = a + b/T + c×ln(T) + d×Te ; where ho = 1 Pa×s