References
- Kujawa, G. V. Veroff Agfa Bd., II, Leipzig. 104 (1931).
- Watter, Otto, Bild und Ton, II, 7th Year, 326 (1954).
- Messrs. Paton Hawksley, Keynsham, Bristol.
- Shirley Developments Ltd., Manchester.
- Marette, Jacques. S. & I.P., 385 (1956).
- Matheson, Andrew. Perspective, 3, 217 (1961).
- Clark, L. D. and Nelson, C. N. Phot. Sci. & Eng., 6, 84 (1962).
- Fromm, H. J. J. Phot. Sci., 10, 147 (1962).
- Lewis, N. W. and Hauser, T. V. J. Phot. Sci., 10, 288 (1962).