(This article appeared in Volume 24, Number 3, Pages 421–425)
Please note the correction to the first line below Eq. (5) on page 422:
For Mb arbitrary and M = 48 (titanium), in a.m.u. unit.
Please note the correction to line seven below Eq. (6) on page 422:
With quasi-classical electrons may be obtained from Cs
Please note the correction to line eight below Eq. (6) on page 422:
Targets at a few eV, in view of its very low Fermi temperature