1. International Standard 1973-12-01., Ref. No. 150, 1069?1973 (E/F).
2. E. G. Shramkov, Izmer. Tekh., No. 7 (1973).
3. L. A. Sena, Units and Dimensions for Physical Quantities [in Russian], Nauka, Moscow (1969).
4. R. Feynman, A. Layton, and M. Sands, The Feynman Lectures on Physics, No. 7, Addison-Wesley.
5. F. J. Lowes, Geophys. J. R. Arts Soc.,37 (1974).