1. B. Noble, “The Wiener-Hopf Technique”, Pergamon Press, Oxford (1950).
2. B. Davison, “Neutron Transport Theory”, Oxford University Press (1957).
3. M. M. R. Williams, “Mathematical Methods in Particle Transport Theory”, Butterworths (1971).
4. K. M. Case, “Ann. Phys.” (NY) 9, 1 (1960).
5. C. Cercignani, “Ann. Phys.” (NY) 20, 219 (1962).