1. J.F. Coplin, Proc. Int. Conf. Designing with Titanium, Bristol, 1986, p. 11.
2. R.I. Jaffee, Proc. Int. Conf. Designing with Titanium, Bristol, 1986, p. 28.
3. J.A. Hall, Proc. 6th World Conf. Titanium, Cannes, 1988, part 1, p. 1.
4. T.W. Farthing, Proc. 6th World Conf. Titanium, Cannes, 1988, part 1, p. 37.