1. D. F. HEATH and J. W. LINNETT, Trans. Faraday Soc. 44, 873 (1948).
2. J. W. LINNETT, D. F. HEATH and P. J. WHEATLEY, Trans. Faraday Soc. 45, 832 (1949).
3. D. F. HEATH and J. W. LINNETT and P. J. WHEATLEY, Trans. Faraday Soc. 46, 137 (1950).
4. W. H. FLETCHER and C. E. BAILEY, Ph. D. dissertation, University of Tennessee (1959)