If based from the equation:

Cp/R = a + bT + cT³ + dT^-2

delta h will have the formula

delta h = R (a (T-Tref) + b/2 (T² - Tref²) + c/3 (T³ - Tref³) - d (1/T - 1/Tref))

Hence, what will be the formula of delta h, when:

Cp/R = a + bT +c/T + dlnT + eT²