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Help with Referencing: Citing sources in APA

How do I cite my sources?

Do I need to cite common knowledge?

You do not need to cite things which are considered common knowledge.

Common knowledge is information which is generally known by the average person and can be found in many sources. Examples could include:

  • London is the capital city of the United Kingdom. 
  • Water freezes at 32 degrees Fahrenheit

Be mindful that what may be common knowledge in one nation, culture or academic discipline may not be in another. You should consider whether something is likely to be common knowledge to the audience of your work. 

If you are unsure whether something is common knowledge, it is best to cite it or to check with your tutor.

Citing authors with example references

If you cite a source with one author or editor, cite and reference the author.

Philips (2006)
Philips, D. (2006). Quality of life: Concept, policy and practice. London: Routledge

If you cite a source with two authors you should cite and reference both authors.

(Kimball & Ross,  2002)
Kimball, R., & Ross, M. (2002). The data warehouse toolkit:The complete guide to dimensional modeling. New York: Wiley.

 If you cite a source with three, four or five authors you should cite all in the first citation. Subsequent citations should include the first author followed by et al. In you reference list you should reference all authors.

(Greenstreet, Greenstreet & Schermer, 2011)
Greenstreet, B., Greenstreet, K. S., & Schermer, B. L. (2005). Law and practice for architects. Oxford: Architectural.
(Bott, Coleman, Eaton & Rowland, 2001)
Bott, F., Coleman, A., Eaton, J., & Rowland, D. (2001) Professional issues in software engineering (3rd ed.). London: Taylor and Francis.
(Styner, Greig, Leiberman, Jones & Weinberger, 2003)
Styner, M., Gerig, G., Leiberman, J., Jones, D., & Weinberger, D. (2003). Statistical shape analysis of neuroanatomical structures based on medical models. Medical Image Analysis, 7(3), 207-220.

Works with six or seven authors, you cite the first author followed by et al. and in your reference list you reference all the authors.

(Shepperd, et al., 2009)
Shepperd, S., Doll, H., Gowers,S., James,A., Frazel,M., Fitzpatrick, R., & Pollock, J. (2009) Alternatives to inpatient mental health care for children and young people. The Cochrane Library, (2), article number CD006410.

Works with eight or more authors, cite the first author followed by et al. Include the first six authors, link with ... then add the last  author in your reference which will be added to your reference list.

(Mali, et al., 2013)
Mali, P., Yang, L., Esvelt, k., Aach,J., Guell, M., Dicarlo,J., ... Church, G. (2013). RNA-guided human genome engineering via Cas9. Science, 339 (6121), 823-6.

A source can be written by a corporate author such as an organisation or a company. The corporate author and year should be used in the citation.

In the report by British Airways (2003) it can be seen that...

If you cannot identify the author(s) of a source, cite it by title and list it under the title in your reference list.

In the Dictionary of Biology (2004)...
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