1 P.. Taylor, D.. Gregory, G.H. Dunn, R.A. Phaneuf, and D.H. Crandall, Physical Review Letters 39, (1977).
1 B.. Van Zyl, G.E. Chamberlain, G.H. Dunn, and S.. Ruthberg, Journal of Vacuum Science and Technology 13, (1976).
1 D.H. Crandall, G.H. Dunn, A.C. Gallagher, D.G. Hummer, C.V. Kunasz, D.A. Leep, and P.O. Taylor, Astrophysical Journal 191, (1974).