International journal of multiphase flow 31 (2005) 93

Recently Reeks (2005) published a paper in International Journal of Multiphase Flow where he compared the Advection Diffusion Equation (ADE) approach and the two-fluid model approach based on the PDF method for particle dispersion in inhomogeneous turbulence. Because of the lack of references in Reeks (2005) a reader may get the wrong impression that the author of Reeks (2005) was the first who (1) derived a drift term in the equation for the mean particle mass flux associated with the compressibility of the particle velocity field caused by their inertia, (2) considered the compressibility of the particle velocity field along a particle trajectory, and (3) derived the equation for particle mean mass flux containing higher order spatial derivatives. However, the real situation is completely different.