In the Vancouver system, the only indication required in the text of a paper is a number, allocated in ascending sequence and presented in the text either in brackets or in superscript.

If the same source is cited again later in the text, the same number is used again. The original number assigned to the reference is reused each time the reference is cited in the text, regardless of the previous location in the text.

When quoting directly from a source word for word, quotation marks MUST be used.

To cite two references at the same time, include both reference numbers:

To cite more than two consecutive references at once, just indicate the range:

If you are citing a mixture of consecutive and non-consecutive references, then indicate specific references and ranges as appropriate, in numerical order:

Secondary referencing

Secondary references should be used sparingly. In most cases you should cite material you have actually read.

Occasionally you will read a journal article or book that refers to another source. Ideally you should locate and read this original source – this is recommended. You will then be able to cite the source directly. Sometimes you are unable to obtain the original source to read it. If this is the case, you should acknowledge that you have not consulted the original source. Instead, use the following format in your text: