@staticmethod
def T4_p(p):
    """function T4_p = T4_p(p)

        Section 8.2 The Saturation-Temperature Equation

        Eq 31, Page 34
        """
    beta = p ** 0.25
    E = beta ** 2 - 17.073846940092 * beta + 14.91510861353
    f = 1167.0521452767 * beta ** 2 + 12020.82470247 * beta - 4823.2657361591
    G = -724213.16703206 * beta ** 2 - 3232555.0322333 * beta + 405113.40542057
    D = 2 * G / (-f - (f ** 2 - 4 * E * G) ** 0.5)
    return (650.17534844798 + D - ((650.17534844798 + D) ** 2 - 4 * (-
        0.23855557567849 + 650.17534844798 * D)) ** 0.5) / 2
