1. See, for example, C. W. Chu and M. K. Wu, High Pressure in Science and Technology, Part 1, ed C Homan, R. K. MacCrone and E. Whalley (Amsterdam: North Holland, 1983), p. 3;.
2. C. W. Chu, P. H. Hor and Z. X. Zhao, Physica B 139-140, 439 (1986).
3. See, for example, R. J. Wijngaarden and R. Griessen, Studies of High Temperature Superconductors, vol. 2, ed. by A. Narlikar (Nova Science, 1989) p. 29.
4. R. J. Wijngaarden and R. Griessen, High Pressure Research 5, 874 (1990).
5. C. W. Chu, P. H. Hör, R. L. Meng, L. Gao, Z. J. Huang and Y. Q. Wang, Phys. Rev. Lett. 58, 405 (1987).