1. Bethe, H.A., Ashkin, J., in: Experimental Nuclear Physics (E. Segre, ed.), New York: John Wiley and Sons, Inc., London: Chapman and Hall, Limited, 1953.
2. Lazareva, L.E., Feinberg, E.L., Shapiro, F.L.: Zh. Eksp. Teor. Fiz. 29 (1955) 381.
3. Bergman, A.A., Isakov, A.I., Murin, I. D., Shapiro, F.L., Shtranikh, I.V., Kazarnovsky, M.V., in: Proc. Int. Conf. on Peaceful Uses of Atomic Energy, Geneva 1956, v. 4, p. 135.
4. Gibbons, J.H., Macklin, R.L.: Phys. Rev. 114 (1959) 571.
5. Curtiss, L.F.: Introduction to Neutron Physics, New York: D. Van Nostrand Co, 1961.