Your reference style should be consistent throughout your text. And, of course, references should be accurate – sloppy referencing will quickly detract from your text and from you as author.

How you cite and format references in your text, in endnotes or footnotes or in a bibliography often depends on the convention in your subject and any guidelines for publication. If no guidelines are given, the best advice is to follow a standard work in your field.

Below is a short checklist for referring consistently:

  • Are all the references in your text listed in the bibliography, footnotes or endnotes?
  • Do the names of authors and dates in the text match those in the bibliography or notes?
  • Are your references in order, for example alphabetical order or in order of citation?

References should be formatted consistently. Decide, for example

  • Whether to use and or & for co-authors:
  • Watson and Crick
  • Watson & Crick
  • Whether to use et al. for multiple authors:
  • Smith et al. (2013: 266)
  • Smith, Jones and Green (2013: 266)
  • Whether to separate references in the text by commas or semicolons:
  • Smith (2013:20), Jones (2014:345), Green (2015:45)
  • Smith (2013:20); Jones (2014:345); Green (2015:45)

Names and initials

There are several ways of writing names and initials, with or without a full stop GB or period US, and with or without spacing. All of these styles are fine; however, as always, you should follow any guidelines for your subject or publication and be consistent throughout your text. A number of formats are illustrated below:

T. S. Eliot Eliot, T. S.
T S Eliot Eliot, T S
TS Eliot Eliot TS
T.S. Eliot Eliot, T.S.

Some publications prefer names to be given in full in references:

Eliot, Thomas Stearns
Rowling, Joanne
Tolkien, John Ronald Reuel

pp., ll. and ff.

The abbreviations p. and pp. mean page and pages respectively, for example:

p. 64 page 64
pp. 64–78 pages 64–78

And l. and ll. mean line and lines respectively, for example:

l. 64 line 64
ll. 64–78 lines 64–78

When referring to page or line numbers, if you abbreviate, abbreviate sensibly so that the reference is unambiguous. For instance, for pages 112 to 117:

Not: pp. 112–7
Better: pp. 112–17

The abbreviations f. and ff. mean and the following page(s) or line(s), for example:

64f. pages or lines 64–65
64ff. pages or lines 64 onwards

Subjects and publishers vary in the extent to which f. and ff. are used, with many preferring page or line numbers to be written explicitly and unambiguously.

Special references

The list below gives a number of special types of reference:

Publications by the same author(s) in one year

Smith (2014a), (2014b), (2014c)

Work in draft form

Smith (work in progress)
sometimes with the proviso Please do not cite

Work submitted for publication

Smith (manuscript submitted)

Work due to be published

Smith (forthcoming)

Work about to be printed

Smith (in press)

A publication with no date

Smith (no date)
sometimes abbreviated as n.d.

Unpublished data or information

Smith (unpublished observation)

Personal communication

Smith (2014, personal communication)
refers to unpublished information, for example an interview, telephone conversation, letter or email

Data not shown

(not shown) or (data not shown)
refers to data omitted from the text, e.g. for the sake of brevity

Cited by another author

cited in Smith (2014:123)
refers to a work or data cited by another author, for example if you are unable to access the original

Reviewed by another author

reviewed in Smith (2014:123)
refers to a review by another author

Following another author

following Smith (2014:123)
shows that you have used Smith’s method or approach

following Smith (2014:123) with modifications
shows that you have used a modified form of Smith’s method or approach

adapted from Smith (2014:123) or after Smith (2014:123)
refers to a figure by Smith that you have used in modified form

Translated from another language

Schmidt (2014:123) (my translation) or
Schmidt (2014:123) (translated from German, your initials)
refers to a quotation that you have translated

Referring to digital sources

The following information should be included in references to digital sources:

  1. Author or authors
    2. Document or web page title
    3. Exact web page address
    4. Date of publication or date last updated
    5. Date you accessed the document, for example Accessed 19 February 2014. This is particularly important if no publication date or date last updated is given.

Referring to figures and tables

When referring to figures and tables in your text, it is usually best to use reference numbers rather than above, below, the preceding or the following. This is because figures and tables may be repositioned in the final layout of your text. When sending a paper for publication, the usual phrase to indicate to the editors where you wish your figure to go is:


Referring to equipment

In many subjects it is common to specify the equipment used in a study. In such references, you should be consistent throughout your text, including:

  • Manufacturer’s name
  • City
  • State or province abbreviation for the US and Canada
  • Country

Latin terms in references

A number of Latin terms are used in references. However, with the exception of et al., there is a tendency in many subjects today to give clear unambiguous references with fewer Latin abbreviations.

et al.

The Latin abbreviation et al. means ‘and others’. It is used to refer to three or more authors or editors of a work, for example Smith et al. could refer to Smith, Zhang and Patel, or Smith, Cohen and Martin.

Subjects and publishers vary in the extent to which et al. is used, for example they may prefer all authors to be listed rather than abbreviated with et al., particularly in a bibliography.

Sometimes et al. is written in italics, sometimes not. Either style is fine. However, as always, you should follow the guidelines of your target publication and be consistent throughout your text. Often, et al. is written with a full stop GB or period US after al, but never after et (which simply means ‘and’ in Latin).


The Latin abbreviation ibid. means ‘in the same place’. It is used to refer to a reference immediately above, particularly in notes:

  1. Hamlet, III.i
    2. Ibid.
    3. Ibid., line 58

As it can be ambiguous, subjects and publishers vary in the extent to which ibid. is used.

op. cit.

The Latin abbreviation op. cit. means ‘in the work already cited’. It is used to refer to an earlier reference to an author; for example Shimizu, op. cit. refers to a previous reference to the work by Shimizu.

Subjects and publishers vary in whether op. cit. is used as it can be ambiguous, particularly if there is more than one work by the same author.