1. ISO (1993) “Guide to the expression of uncertainty in measurement”. Geneva, Switzerland. (ISBN 92-67-10188-9)
2. Eurachem/CITAC Guide (2000) “Quantifying uncertainty in analytical measurement”, 2nd edition. Williams A, Ellison SLR, Roesslein M (eds). Available from the Eurachem secretariat and website ( http://www.eurachem.com/ ) and (hard copy) LGC Ltd, London (ISBN 0-948926-15-5)
3. Kragten J (1994) Analyst 119:2161–2166
4. Haesselbarth W, Bremser W (2004) Accred Qual Assur 9:597–600
5. Press WH, Flannery BP, Teukolsky SA, Vettering WT (1988) Numerical recipes in C. Cambridge University Press, Cambridge NY, p 272.