1. R. T. Johnson and J. C. Wheatley,J. Low Temp. Phys. 2, 423 (1970).
2. J. C. Wheatley, inProc. of the 2nd Intl. Conf. on Polarized Targets, Gilbert Shapiro, ed. (National Technical Information Service, U.S. Department of Commerce, Springfield, Virginia, 1971), p. 73.
3. J. M. Daniels, p. 77.
4. S. D. Baker, p. 85.
5. J. C. Wheatley, p. 413.