Skip to Main Content
It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.

ACG Series: Citations: Unit 2

In this Academic Communication Guide, learn about the basics of citations and some common citation styles and tools.

Unit 2: Citations - What do I cite? When should I cite?

Unit Objectives:  

At the end of this ten-minute unit, you will be able to:  

a) identify the types of information that need to be cited 

b) identify the types of information that do not need to be cited, and 

c) know when to provide citations in your work.  

Unit 2 Contents

What needs to be cited?

1. Interviews and conversations

2. Visuals

3. Social media posts

What does not need to be cited?  

1. Generally accepted facts

2. Common knowledge

3. Personal experiences

4. Results obtained through lab or field experiments  

5. Your own content

Quick Check

Unit Summary

What needs to be cited?

As previously explained, you need to provide a citation when you are using the words or ideas of another author or entity. Keep in mind that this is not limited to words or ideas published in written documents, but also includes conversations, interviews and any multimedia communication or expression. The following list provides some examples of these and is not exhaustive. 

1. Information from interviews and conversations  

An assignment may require you to conduct an interview, be it in person or otherwise. As the responses that you record are not your own thoughts, words or ideas, you must attribute them to the interviewee within the text. In this case, an in-text citation is required, but a listing in the reference list is not. Personal communications, such as an interview or conversation, rarely appear as bibliographic entries in the reference list. Moreover, to safeguard the privacy of your respondents, you should be careful not to include email addresses or other contact information through which the communication was conducted unless it is necessary and you have the source’s permission (Purdue Online Writing Lab, n.d.).  

Example of personal communication in-text citation (APA style): 

Text Box 

2. Visuals  

It is mandatory to credit or document sources when you use any diagrams, illustrations, pictures, or other visual materials (University of Cincinnati Libraries, 2021). This should be done for all forms of assessments, including PowerPoint slide decks. As shown in the previous and following picture, even if the visual is free to use, it is recommended to credit the creator or publisher.  

The following picture is from Unsplash, which is a great resource for free-useable images. Though Unsplash does not require users to provide citations for the pictures from their website. It is recommended that you provide an in-text citation to give the creator credit for their work (as seen under the next picture). As in-text citations work in tandem with the reference list, you should also provide a corresponding entry in your reference list.














Credit: Green Chameleon (2015) 

Example of a reference list entry in APA for a free-to-use image  

Green Chamelon. (2015). Person writing on a brown wooden table near a white ceramic mug [Stock image]. Unsplash.  

3. Social media posts 

Content taken from social media sites, such as Facebook, Instagram, Twitter and Quora, are considered forms of electronic content that may include text, images and audio-visual content. Though sharing of posts may be commonplace on these social media sites, you should try as best as possible to directly cite the original source. Below is an example of a citation of a Tweet (Auckland University of Technology, 2021).  


Example of a citation (in-text and reference list) of a social media post in APA 

In-text citation  

Arden (2015) tweeted her appreciation for…  

Reference list 

Ardern, J. [@jacindaardern]. (2018, October 15). I salute you, @Kereru4PM #BirdOfTheYear [Tweet]. Twitter. 

What does not need to be cited?

Knowing what does not need to be cited can also help you better identify what needs to be cited.  

1. Generally accepted facts  

The first type of information that does not need to be cited is generally accepted facts. The reason for this is that it is quite difficult, if not impossible, to attribute these facts to a specific individual or source. This includes facts that are generally accepted within specific discourse communities. For instance, ‘smoking is bad for health’ is a generally accepted fact in the scientific community. However, do note that you must cite specific findings that support these generally accepted facts. Take a look at the following example for a clearer distinction between these two. Here, the phrase highlighted in yellow is considered to be a generally accepted fact, whereas the phrases in green are findings that are taken from a source.   


Example of a generally accepted fact and a finding from Benowitz (2009) 

Use of nicotine sustains tobacco addiction, which in turn causes devastating health problems, including heart disease, lung disease, and cancer, and increased susceptibility to a variety of infectious diseases. Smoking harms almost every organ of the body [1]. Quitting smoking at any age leads to significant reductions in the risks associated with it, and the vast majority of smokers in the United States indicate an interest in quitting [2].  

2. Common knowledge  

According to University of Cincinnati Libraries (2021), types of common knowledge include folklore, common sense observations, myths, urban legends and historical events (but not historical documents). The following table provides examples of these types of common knowledge.  

 Type of Common Knowledge 



 Kusu Island is believed by some to have been a giant tortoise that turned into an island to save a group of fishermen. 


 Sang Nila Utama threw his crown into the sea to stop the storm. 

 Common sense observation 

 Singapore is a multiracial country. 

 Historical events 

 Singapore gained independence on 9 August 1965. 


In contrast, you would need to cite the source if you were, to for example, add the following phrase in your paper, as it is from a historical document: 

Text Box 

Nevertheless, it can be quite difficult to determine what is considered to be common knowledge, or for the matter a generally accepted fact. Therefore, if you are in doubt, it may be a good idea to err on the side of caution and provide a citation.  

3. Personal experiences  

Personal experiences that do not need to be cited comprise ‘your own observations and insights, your own thoughts and your own conclusions’ (University of Cincinnati Libraries, 2021). This is because these are your own work. You can see an example of this below.  


Example of a student’s thoughts about a source  

One commonly used form of therapy for HIV infection is the Highly Active Antiretroviral Therapy (HAART), which includes the usage of two or more ARV drugs (Ezhilarasan et al., 2017). However, taking such ARV drugs can have many severe side effects. A previous study by Ravimohan et al. (2020) has shown that ARV drugs can lead to a decrease in lung function in patients with Tuberculosis. Nonetheless, there needs to be more information on whether long-term usage of ARV drugs will speed up the process of deterioration in younger patients.  

4. Results obtained through lab or field experiments  

You do not have to provide a citation when you are reporting the results from your own experiments for the first time, because these findings are yours. However, you must cite the original source when you adapt a method or approach, or when you are comparing your results to findings from other scholars.  


Example of a citation for an adapted survey question  

In Johnson’s (2014) original survey, the researcher asked participants to indicate the number of times they had fast food each week. However, for the purpose of this study, the participants were asked to state the frequency of which they had fast food and hawker centre fare in any given week.  

5. Your own content  

The last type of information that does not need to be cited is your own original content as you are the creator. This encompasses digital photographs, videos, audio clips and even drawings. Nevertheless, if your content is heavily inspired or adapted from a source, you should give due recognition to the original piece.  

Quick Check

1. Does the student in the following scenario need to provide a citation?  

Anna was a final year business student. She interviewed her cousin, who was working for a local bank, for her final year project. Two weeks later, she sent her cousin two follow-up questions on WhatsApp and added the replies to her transcript.  

2. Do you have to cite the following story if you were to mention it in your essay?  

Sentosa was formerly known as Pulau Belakang Mati (literally ‘island of death behind’ in Malay). Some believe that the island was given its name due to its dark past. It has been said that the island was the burial ground for many ancient Malay warriors.   


Answers to the questions can be found on the 'Answers' tab.

Unit Summary

Well done! You have finished the second unit of this module. You have learnt that you must provide a citation when you incorporate quotations from personal communications, visuals taken from online sources and information from social media posts in your assignments. This is because these are examples of information that are not your own original thoughts or ideas. You have also learnt that there are types of information that do not need to be cited. These include generally accepted facts, common knowledge, personal experiences, your own laboratory results, and generally any other content that you create. The reason for this is that the information cannot be attributed to a specific source or that it belongs to you.