1. University of Durham, Improvements in and relating to crystal growth, U.K. Patent Application No. 9717726.5, 1997.
2. J.T. Mullins, J. Carles, N.M. Aitken, A.W. Brinkman, to be published.
3. Congruent (diffusionless) vapor transport
4. F. Rosenberger, M. Banish, W.M.B. Duval, Technical Memorandum 103786, NASA (1991).