When you write an essay, conduct research, or work on a portfolio assignment, you always make use of various academic or internet sources. Since you cannot simply copy information someone else has written, it is mandatory to add references to the original sources. Not doing this makes you guilty of plagiarism. Another reason why you have to cite the sources you use inside your text is that it ensures that the reader can find and check the information you write in your report. Therefore, source citations are almost always an obligation from your college or university. Several methods of source citations are accepted in the academic world. The most used method of in-text source citations is called APA.

APA rules source citations

There are several rules attached to APA source citations. First of all, the author, year, and page numbers (if your source is a book) are mentioned in the text by default. Next, a source list is made, which you place at the end of your report. Additional information such as the book's publisher or the source's link will be mentioned here. Stuvia has listed the most important APA rules for source citations for you, so you can apply them to your reports without errors.

In brackets or narrative citations?

There are two ways to introduce a source in your text. You can choose to put the source in brackets or use narrative citations. But what exactly does that look like? With a source in brackets, you put both the author's surname and the year in brackets. With a narrative citation, you place the author's name in the sentence and only put the year in the brackets. In the examples below, you can see exactly how this looks:

Sources with multiple authors

Sometimes a book or other source is written by two different authors. In this case, join the surnames together by adding an '&' or 'and'. For three or more authors, write only the surname of the first author, followed by 'et al'. You may also use a group of authors, such as Stuvia or Statistics Netherlands, as a source. In this case, put the name of the group in brackets.

If the name can be abbreviated, such as CBS, only give the full name the first time, but put the abbreviation in text brackets. For the times after that, you can just use the abbreviation between the brackets or in the text. In the diagram below, we show how APA source citations with different numbers of authors will look in your text:

Unknown author or date

The author or date of your source may not be known. Fortunately, this does not matter at all! When the author of your source is unknown, choose the title of the document (37 relevant trends for communication, 2021) or the name of the organization behind the document (Stuvia, 2021). Make sure the title and organization are also included in your source list.

When the publication date of the source is unknown, write 's.d.' in the reference. This means without a date, for example, Stuvia (s.d.).

Avoiding ambiguity

There are some ambiguous situations you may encounter when writing your assignment while referring to your sources. We have briefly listed the most important ones for you so you know how to resolve them:

• Two or more sources by the same author in the same year:

You can easily solve this situation by adding a lowercase letter to your APA source citation in your text after the year. You then use (2022a) or (2022b).

• Authors with the same surname

There are also rules in the APA source citation for this situation. In this case, you add the initials (initials) of the author, for example, J. Meijer and G. Meijer.

Referring to a source within a source

This is also called an indirect reference. Sometimes, when searching for specific information, you find a study made by someone else. In this case, you always look for the primary source, also known as the original source. This ensures that the reader gets the right context to your information. If you cannot find it, it is advisable to look for another source that provides the same information.

Source citation personal communication

Many studies require you to conduct interviews with the target audience or experts for your thesis or other reports. These will not be included in your topic list, but they should be referenced in your text using APA source citation. In this case, first put initials with the surname in brackets, followed by the form of communication and the exact date. In most cases, the form of communication will be an interview, but it can also be an e-mail or telephone conversation.

How often to cite a source?

You may use a source several times for your essay, thesis, or another school assignment. Still, it is important to indicate to the reader where exactly you got the information. You do this in the following way:

• In a narrative citation of a source, you indicate both the author and the year in the first reference. If you then continue with the source, you no longer need to place a narrative citation here;
• In the case of a reference in brackets, place the reference at the end of the text your source is about. Should you use the source again, later on, you place it here again. Make sure you do not mention a source too often, but also not too little.
  

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