This lecture focuses on deriving the Kalman-Hauad-Morning relation in the context of stationary turbulence with a forcing term. The instructor explains the importance of homogeneity and isotropy assumptions, as well as the implications of stationarity for the velocity field and forcing term. Through detailed mathematical derivations, the lecture explores the third order structure function and its divergence, leading to the derivation of the common Howard-Mohnen relation for homogeneous but not isotropic cases.