1. Sir Henry Bessemer, F. R. S., An Autobiography, Engineering, London (1905), p. 68.
2. D. R. P. 154,998.
3. G. Naeser and F. Zirm, Stahl Eisen 70:995 (1950).
4. British Provisional Pat. No. 34541/53.
5. P.E. Evans, Ph.D. dissertation, The Continuous Compaction of Metal Powders, Cambridge University (1956).