Axford, W. I. MPI for Aeronomy, Max Planck Institute for Solar System Research, Max Planck Society;
Axford, W. I. (1981). Acceleration of cosmic rays by shock waves. In Proc. International School and Workshop on Plasma Astrophysics, Varenna, 27 August-07 September 1981 (pp. 425-449). Noordwijk: ESA Publ. Div.