There are differing approaches to the presentation of citations depending on the number of authors in the source.
| One author: | 2 authors: | 3 authors: | 4 or more authors: |
|---|---|---|---|
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The citation shows the author’s surname and year of publication.
(Barrett, 2020).
|
The citation shows both authors’ surnames and the year of publication.
Barrett and Collins (2019) discuss…. |
The citation shows all 3 surnames and the year of publication.
(Barrett, Collins and Doyle, 2021) |
Write the first author's name in your in-text citation followed by ‘et al.’. Your reference list includes the names of all the authors.
Barrett et al. (2023) stated that … |
Note: When referencing a chapter of an edited book, your in-text citation should give the author(s) of the chapter. Both editor(s) and chapter author(s) will be included in the Reference list.
|
Author has published more than one cited source in the same year |
Same author written in different years
|
Source written by 2 authors with the same surname in the same year
|
Author unknown
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|---|---|---|---|
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These are distinguished by adding lower case letters (a,b,c, etc.) after the year and within the brackets:
(Byrne (2023a) discussed … and Byrne (2023b), in further research on this, came to the conclusion that …).
Each citation should have a matching reference in the reference list.
Byrne, M. (2022a) Viral infections. Dublin: ABC Publishers. Note: This only applies if you are citing the same author and year across several sources; otherwise, there is no need to append a letter to the date if you are citing the same source more than once. You just need to cite the source once in your reference list and it will always have the same citation format. |
If you need to refer to two or more sources by the same author in different years, there is no need to keep repeating the author's surname in the citation.
Include the surname and the oldest year first, then separate the other years by semicolons (;). The sources should be ordered by year of publication, with the oldest first.
(Brady, 2019; 2021; 2024).. You must include all of the sources separately in your reference list or bibliography. |
If two or more sources have authors with the same surname and were written in the same year, they should be distinguished by including the authors' initials in the relevant citations.
The phenomenon of red and yellow autumn leaves is a good indication of being climate-specific (J. O’Connor, 2020) and, in further research, M. O’Connor (2022) found that….. |
If there is no named author, use the name of the organisation.
(Health Service Executive, 2023). If the organisation is known by abbreviations, always give the name in full the first time their work is cited. The abbreviations can be used in subsequent citations. … in news on Raidió Teilifís Éireann (RTE, 2024). If the author's name is unknown, you should give the title of the source, in italics.
(Microplastics found in testicles, 2024).
If the work is a journal or newspaper article, use the name of the journal or newspaper.
(The Irish Times, 2024). |