1. A. G. Leatham, R. G. Brooks andM. Yaman, in ?Modern Developments in Powder Metallurgy?, Vol. 15 (MPIF, New Jersey, 1985) p. 157.
2. Osprey Metals Ltd, UK Pat. 147 239.
3. G. J. Marshall, in ?Proceedings of the International Conference on Aluminium Technology '86?, London, March 1986, edited by T. Sheppard (The Institute of Metals, London, 1986) p. 679.
4. J. L. Estrada andJ. Duszczyk,J. Mater. Sci. 25 (1990) 1381.
5. P. Mathur, S. Annavarapu, D. Apelian andA. Lawley,J. Metals 41 (1989) 23.