1. K. Prelec, Proc. Symp. on the Production and Neutralization of Negative Ions and Beams, BNL 50727, p. 111, 1977.
2. Z. W. Sternberg, BNL Int. Report AGS 77-4, 1977.
3. Iu. I. Belchenko, G. V. Dudnikov, preprint 1Yaf-78-95.
4. M. W. Grossman, Proc. Symp. on the Production and Neutralization of Negative Ions and Beams, BNL 50727, p. 105, 1977.
5. K. Prelec (private communication).