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Leeds Numeric introduction

Common issues when using Leeds Numeric

When you're referencing with Leeds Numeric you may come across issues with missing details, multiple authors, edited books, references to another author's work or online items, to name a few. Here are some tips on how to deal with some common issues when using Leeds Numeric.

Skip straight to the issue that affects you:

Online items

You should reference the actual version of the item that you have read. This is especially important for items which are published both online and in print format as page numbers and other information may be different. The exception to this rule are journal articles, which should not be referenced as online items.

These three pieces of information should be included whenever you reference something you read online (except journal articles):

  • [online]
  • the URL
  • the date you accessed the article.

Example for an online book:
Hollensen, S. Global marketing: a decision oriented approach. [Online]. 5th ed. Harlow: Financial Times Prentice Hall, 2011. [Accessed 10 September 2018]. Available from:

If you download or read a PDF from a website, you must reference the actual document type, for example a book chapter, a government report or a leaflet, not the file format (eg PDF).

URL web addresses

Ensure that you are using the URL (web address) of the actual source document, and not the URL of the Library search result or other search engine (ie Google). URLs from Library search results have the words "primo.exlibrisgroup" in them.  

If you are using a reference manager such as EndNote or Mendeley, it is important to check the URL on items you have imported from databases or search engines, and amend it to the URL of the source document (rather than the database or search engine) where necessary. 

Multiple authors

You should include all author names in the reference. Where a source has a very long list of authors, eg in the case of some scientific articles, you might wish to consult your tutor on whether to use "et al." in place of some author names.

Two authors

If the source has two authors, you should include both authors in the reference.

Follow the format: Family name, INITIAL(S). and Family name, INITIAL(S). Title. Edition (if not first edition). Place of publication: Publisher, Year.

Example reference:
Ahmed, T. and Meehan, N. Advanced reservoir management and engineering. 2nd ed. Amsterdam: Gulf Professional Publishing, 2012.

Three or more authors

If the source has three or more authors, you should include "and" before the final author name.

Family name, INITIAL(S)., Family name, INITIAL(S). and Family name, INITIAL(S). Title. Edition (if not first edition). Place of publication: Publisher, Year.

Clayden, J., Greeves, N. and Warren, S. Organic chemistry. 2nd ed. Oxford: Oxford University Press, 2012.

Citing in the text

If you refer to two or more sources at the same time, these can be cited together. The numbers of the sources are placed inside one pair of brackets, separated by commas.

For example:
With road transport set to grow by 33% over the next 20 years (2, 3), it is important for governments, businesses and individuals to act now to reduce the impact that transport is having on the global environment (7, 12, 35).

If you refer to three or more different sources at the same time and they have consecutive citation numbers, eg 3, 4 and 5, a dash can be used to abbreviate this.

With road transport set to grow by 33% over the next 20 years (3-5)...

The dash indicates that number 4 is also being cited.


If you are referencing a book with an editor rather than an author, this should be indicated in the reference.

Follow the format: Family name, INITIAL(S) (of editor). ed. Title. Edition (only if not first edition). Place of publication: Publisher, year.

Example references:

  • Crandell, K.A. ed. The evolution of HIV. Baltimore: Johns Hopkins Press, 1999.
  • Wexler, P., van der Kolk, J., Mohapatra, A. and Agarwal, R. eds. Chemicals, environment, health: a global management perspective. Boca Raton, FL: CRC, 2012.

For an edited book with chapters written by different authors, see Book chapter (in an edited book)

Corporate author(s) or organisation(s)

If the item is produced by an organisation, treat the organisation as a "corporate author".

This means you can use the name of the organisation instead of an individual author. This could include government departments, universities and companies.

For example:
Department of Health. Winter flu vaccination begins. [Online]. 2011. [Accessed 19 October 2011]. Available from:

Multiple publisher details

If multiple publishers are listed, you should include only the first publisher listed, (or the British one if it is a choice between a UK and an overseas publisher) in your reference list or bibliography.

Multiple places of publication

If multiple places of publication are listed, you should use the first place name given when writing your reference list.

If there is a town and county/state on the title page, you should just give the town. However, if there is more than one well-known town of that name, you might want to give the state as well to make it clear.

For example:
Stern, D.N. The first relationship: infant and mother. Cambridge, Mass.: Harvard University Press, 2002.

Editions and reprints

You should reference the year your edition was first published. Don't include any subsequent reprint dates, unless the publisher has changed, in which case you should reference the first date of publication of the new publisher's edition.

Example of a book reprinted by a different publisher (see the different editions in the library catalogue):
Achebe, C. Things fall apart. London: Penguin, 2006.

Missing details

No author

First check whether there is a corporate author. If there is no individual or corporate author it is acceptable to use Anon.

No date

If you are referencing a book which has only a copyright year, you can use this date preceded with a "c", for example: c2008.

If there is no publication date and no copyright date, use [no date].

For example:
Jones, M. Citations and referencing. London: Longmans, Green and Co. [no date].

Approximate dates

If you are referencing something with an approximate date of publication/creation, use the date preceded by ca.

For example:
Le Sueur, E. Alexander and his doctor. [Oil on canvas]. ca. 1648-9. At: London: National Gallery. NG6576.

No page numbers

Page numbers are normally only included in your reference list or bibliography for a few types of reference, eg journal articles, newspapers, chapters in edited books. If the source has no page numbers, use [no pagination].

For example:
Pajunen, K. Institutions and inflows of foreign direct investment: a fuzzy-set analysis. Journal of International Business Studies. 2008, 39(4), [no pagination].

If you are citing a source that has no page numbers, use (no pagination) in the in-text citation.

For example:
"It was emphasised that citations in a text should be consistent" (1, no pagination).

No publisher or place of publication

If you are unable to identify the publisher, or the place of publication, use [no publisher] or [no place], as appropriate.

The work of one author referred to by another

If the author refers to another author’s work, you should always try to track down the original work. If this is not possible, and you intend to cite the ideas of one author that you have found in the work of another, your text must refer to the original author of the ideas that you are using, and to the source in which you actually found the ideas.

For example, if you were quoting Brown, as cited in a work by Matthews your citation would be "Matthews (1, p.17) cites Brown, who emphasises that citations in a text must be consistent."

Your reference list should only give details of the source in which you actually found the ideas, in this case the work by Matthews.

If the reader wants to find the full reference details of the original work by Brown, they should be available in the list of references in Matthews' work.

Anonymising sources for confidentiality

You should always use the specific template for the format you are using eg report / leaflet / interview etc but sometimes it may be necessary to anonymise sources to maintain confidentiality. For instance, sensitive medical reports, identity of school placements, or legal sources. In some circumstances you could use terms such as ‘Pupil B’ or ‘Placement school’ instead of actual names. The anonymised part of the institution and title should be in square brackets to indicate substitution.

For example:

NHS Trust (Name withheld). Costs and implications of project beta in intensive care. Unpublished confidential document. 2016.

[Placement school]. [Placement school] examination criteria for pupils with dyslexia. Leeds: [Placement school]. 2019.

Identifying the authors’ family name (surname)

If you are not sure how to reference someone’s name correctly, take a look at our helpful tips