1. Spreading of electron beams due to their own space charge;Borries;Arch. Electrotech.,1938
2. A theorem of Larmor and its importance for electrons in magnetic fields;Brillouin;Phys. Rev.,1945
3. On the focusing of high current electron beams;Brewer;J. Appl. Phys.,1954
4. Formation of high density electron beams;Brewer;J. Appl. Phys.,1957
5. The behaviour of an electron beam as it enters a coaxial magnetic field;Brueck;Telefunken-Ztg.,1953