1. K.H. Miska, J. Met., 40 (1988), p. 14.
2. P. Chaudhari, R.H. Koch, R.B. Laibowitz, T.R. McGuire and R.J. Gambino, Phys. Rev. Lett., 58 (1987), p. 2684.
3. P.H. Carr, Microwave J., 31 (1987), p. 91.
4. J.R. Delayen, K.C. Goretta, R.B. Poeppel and K.W. Shepard, Appl. Phys. Lett., 52 (1988), p. 930.
5. K.C. Goretta, I. Bloom, N. Chen, G.T. Goudey, M.C. Hash, G. Klassen, M.T. Lanagan, R.B. Poeppel, J.P. Singh, D. Shi, U. Balachandran, J.T. Dusek and D.W. Capone II, Mater. Lett., vol. 7 (1988), p. 161.