1. Blevin W (1998) National and international needs relating to metrology: international collaborations and the role of the BIPM. A report prepared by the CIPM for the governments of the member states of the convention of the metre. The intergovernmental organisation of the convention of the metre. http://www.bipm.org/utils/common/pdf/blevin1998.zip
2. Kaarls R (2003) Evolving needs for metrology in trade, industry and society: a report prepared for the governments of the member states of the metre convention and associates of the CGPM. The international organisation of the metre convention. http://www.bipm.org/utils/common/pdf/kaarls2003.zip
3. Kaarls R (2007) Evolving needs for metrology in trade, industry and society and the role of the BIPM. The international organisation of the metre convention. http://www.bipm.org/utils/common/pdf/Kaarls2007.pdf
4. Petley B (1985) The fundamental physical constants and the frontiers of metrology. Adam Hilger, Bristol ISBN 0852744277
5. Birge R (1941) A new table of the general physical constants. Rev Mod Phys 13:233–239