1. Aviation Week & Space Review;Foley,1988
2. 10th Int. Conf. on Application of Accelerators in Research and Industry;Schrage,1989
3. Proc. 3rd Symp. on Production and Neutralization of Negative Ions and Beams;Allison,1983
4. C.D. Davis, M.T. Lynch, and D.W. Reid, to be published, Proc. 1989 Particle Accelerator Conf., Chicago, Illinois, USA.