1. Blin, J. and A. Guinier, C. R. Acad. Sci., Paris233 (1951) 1288.
2. Hayes, S., R. Smoluchowski and R. W. Turner, Phys. Rev.90 (1953) 350.
3. Dexter, D. L., Phys. Rev.90 (1953) 1007.
4. Dr. Guinier has kindly informed the authors that the existence of such a crossover has indeed been confirmed.