1. D. Hainsworth, Queensland Institute of Technology Brisbane, private communication (1981).
2. A gas-control unit for use with cathodic-sputtering cells in analytical atomic spectroscopy
3. Cary Principle in Monochromator Design
4. Optronic Laboratories Inc., 7676 Fenton Street, Silver Spring MD 20910, U.S.A.
5. National Measurement Laboratory, Commonwealth Scientific and Industrial Research Organization, Division of Applied Physics, Linfield, N.S.W., Australia.