1. Bear, J., J. Amer. Chem. Soc., 66, 1297 (1944).
2. Guinier, A., and Fournet, G., C.R. Acad. Sci., Paris, 226, 656 (1948).
3. Furnas, T. C., “The Development of Focusing X-ray Cameras for Use at Small Diffraction Angles” (Mass. Inst. Tech. thesis, 1952).
4. Ehrenberg, W., J. Opt. Soc. Amer., 39, 741 (1949).
5. Ehrenberg, W., and Spear, W. E., Proc. Phys. Soc., B, 64, 67 (1951).