Self-Diffusion by Multivariate-Normal Turbulent Velocity Field

A closed set of \textit{exact} equations describing statistical theory of turbulent self-diffusion by multivariate-normal turbulent velocity field is derived. In doing so, we first suggest exact formulas for correlations $<f_i(p)f_j(p')R[{\bf f}]>$, $<g(p)R[{\bf f}]>$ and $<g(p)f_j(p')R[{\bf f}]>$ when the functional $R[{\bf f}]$ is functional of functions ${f_i}$'s having multivariate-normal distribution, $g$ and $f_i$'s have joint normal distribution and zero mean values.