References
- Trabka. E. A., The Theory of the Photographic Process. 4th edn.ed., T. H. James. Macmillan. New York and London. 1977. ch. 21. sec. F.
- Selwyn. E. W. H., Photogr. J., 75, 751 (1935)
- Ohnesorge. A., J. Signal AM., 3, 187 (1978)
- Saunders. A. E., J. photogr. Sci., 29, 51 (1981)
- Pitts, E. J. photogr. Sci., 29, 56 (1981).