17 Notes and references
17.4 Numbered references
Some scientific publications use the author–number (or Vancouver) system, which numbers the citations in a single sequence and dispenses with authors’ names in the references in text; these consist simply of superscript numbers or numbers in parentheses or square brackets, multiple references being separated by commas, set close, with number ranges used as appropriate (as found in similar studies.3, 5, 6, 14–18). This arrangement has a superficial resemblance to endnotes, but the reference numbers do not necessarily occur in numerical sequence in the text, where any one may be repeated several times:
Issues of risk, choice, and chance are central to the controversy over the MMR vaccine that erupted in the UK in 1998 and has continued into the new millennium.1
1. Fitzpatrick M. MMR and Autism: What Parents Need to Know. London: Routledge, 2004.
The inter-individual variability in VO2 measured at a given speed and rate can be as high as 15% .
18. Nieman, D. C. Exercise Testing and Prescription, 5th edn. New York: McGraw-Hill, 2003; 90.