References
- Payne, E. C., Mager, E. L. and Jerome, C. W., III. Eng. 45, 688 (1950).
- Destriau, G., U.S.P. 2 863061, (1958).
- Henderson, S. T., Brit.J.Radiology 31, 313 (1958).
- Ranby, P. W., Electrical Times 144, 341 (1963).
- Ranby, P. W. and Northwood, J. L. B.P. 1185832 (1967).