1) Baird, H. I. M., Senior, M. G. and Thompson, R. J.: Terminal Velocities of Spherical Particles in a Vertically Oscillating Liquid, Chem. Eng. Sci., Vol. 22, pp. 551-557, 1967.
2) Houghton, G.: The Behaviour of Particles in a Sinusoidal Velocity Field, Proc. Roy. Soc., A272, pp. 33-43, 1963.
3) Houghton, G.: Particle Trajectories and Terminal Velocities in Vertically Oscillating Fluids, Can. J. Chem. Eng., 44, pp. 90-95, 1966.
4) Houghton, G.: Particle Retardation in Vertically Oscillating Fluids, Can. J. Chem. Eng., 46, pp. 79-81, 1968.
5) Tunstall, E. B. and Houghton, G.: Retardation of Falling Spheres by Hydrodynamic Oscillation, Chem. Eng. Sci., Vol. 23, pp. 1067-1081, 1968.