Molecular dynamics calculations of the ratio D/DE (where D was the self-diffusion coefficient and DE was the Enskog dense fluid diffusion coefficient) for a dense hard-sphere fluid, were done for the density range corresponding to 1.5 ≤ V/V0 ≤ 4.0 (where V0 was the volume of close-packed hard spheres), for systems of 128, 250 and 432 particles. Values of D/DE at a given density did not differ significantly for 250 and 432 particles, and the values were significantly smaller than those obtained for the same densities by Alder, Gass and Wainwright via application of a hydrodynamic correction to give values for an infinite number of particles. The D/DE values for 250 or 432 particles led to a much better correlation between the Chandler hard-spheres theory and experimental diffusion data for methane than was obtained previously using the infinite system values of D/DE. Self-Diffusion in a Dense Hard-Sphere Fluid: a Molecular Dynamics Simulation. Easteal, A.J., Woolf, L.A., Jolly, D.L.: Physica A, 1983, 121[1-2], 286-92