Vaporization latent heat... how much do you know?

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Also known as the latent heat of evaporation, it is the heat of vaporization. The heat absorbed per unit mass of saturated liquid when it turns into dry saturated vapor under constant pressure conditions. During the vaporization process, the temperature remains at the saturation temperature corresponding to the pressure. So it is a form of latent heat. The latent heat of vaporization for any substance is equal to the difference between the specific enthalpy h″ of the dry saturated vapor at the same pressure and the specific enthalpy h′ of the saturated liquid. The latent heat of vaporization γ can be expressed by the formula γ = h″ – h′. Substances of different types have different values of latent heat of vaporization at the same pressure. For the same substance, the latent heat of vaporization decreases as the saturation temperature increases. For example, at 100°C (with a corresponding saturated pressure of 101 kPa), the latent heat of vaporization is 2257.2 kJ/kg. The latent heat of vaporization at 179.88°C (with a corresponding saturated pressure of 10 MPa) is 2015.4 kJ/kg, while it is zero at temperatures as high as 374.12°C (with a corresponding saturated pressure of 21.69×10 MPa). Can the latent heat of vaporization be found in which standard?