1. 1961 Trans. of the 8th Vacuum Symp. and 2nd Intern. Congress;Schumacher,1962
2. Beam Terminology
3. also J. H. Fink and B. W. Schumacher, The anatomy of a thermionic electron beam, Optik, in print.
4. 1st Intern. Conf. on Electron and ion Beam Science and Technology;Schumacher,1965